The impact 'shocking' halt on US aid to Ukraine could have on war

LONDON -- President Donald Trump directed his administration to "pause" all military aid to Ukraine, two White House officials told ABC News on Monday, following last week's combative Oval Office meeting with Ukrainian President Volodymyr Zelenskyy and with Trump pressuring Kyiv into accepting a peace deal to end Russia's invasion of the country.

The freeze in American aid poses a severe strategic problem for Ukraine, which has become reliant on military and economic support from its Western partners as it tries to repel Russia's three-year-old invasion and stave off President Vladimir Putin's push for a peace deal beneficial to Moscow. Experts say Ukraine and its European partners now produce most of the weaponry destined for the battlefield. But there are crucial American systems that Kyiv will struggle to replace.

In his first comments following Trump's announcement, Zelenskyy -- while not commenting directly on the aid pause -- said Ukraine is ready to come back to the table and sign the minerals deal "in any time and in any convenient format."

"None of us wants an endless war. Ukraine is ready to come to the negotiating table as soon as possible to bring lasting peace closer," Zelenskyy said in a statement. "Nobody wants peace more than Ukrainians. My team and I stand ready to work under President Trump's strong leadership to get a peace that lasts."

ABC News' Rachel Scott, Michelle Stoddart, Shannon Kingston, Luis Martinez and Joe Simonetti contributed to this report.

"We do really value how much America has done to help Ukraine maintain its sovereignty and independence. And we remember the moment when things changed when President Trump provided Ukraine with Javelins. We are grateful for this," Zelenskyy continued, in part.

Regarding the Oval Office meeting last week, the Ukrainian leader said it "did not go the way it was supposed to be. It is regrettable that it happened this way. It is time to make things right. We would like future cooperation and communication to be constructive."

"It's shocking," Oleksandr Merezhko, a member of the Ukrainian parliament and the chair of the body's foreign affairs committee, told ABC News. "Until the last moment I hoped that Trump wouldn't do it because he wants to be popular and such a move would definitely cause a backlash."

"Trump is helping Putin to kill Ukrainians," he added.

A Ukrainian intelligence official told ABC News that the first real effects of the freeze of U.S. military aid will be felt in about two weeks. The most serious difficulties will come in June or July, when ammunition shortages will bite, they said.

The official called the freeze a "black day" for Ukraine and for Europe. European countries, they said, now need to fully open their stocks to Kyiv in order to fill the gap being left by the U.S.

A White House official told ABC News that Trump has been clear that he is focused on peace. "We need our partners to be committed to that goal as well," they said. "We are pausing and reviewing our aid to ensure that it is contributing to a solution."

"It looks like Trump is trying to make a deal with Russia over the heads of Ukraine and Europe at the cost of Ukraine," Merezhko said. "He doesn't apply leverage over the aggressor but is trying to force the victim, the weaker party, to accept demands of the aggressor."

"If Trump has a different plan in mind he should have at least talked to Zelenskyy about it behind closed doors, which never happened," the lawmaker said.

Fellow member of parliament Oleksiy Goncharenko told Sky News that "thousands of people will die" due to the "catastrophic" decision.

Ukrainian Prime Minister Denis Shmyhal told a press conference that Kyiv is "working to ensure the support of the Ukrainian Armed Forces. We are grateful to the United States and the American people, who have supported and continue to support Ukraine for the past three years. Today, that support continues."

"We will calmly continue our work with the U.S. -- with Congress and the Trump administration -- to continue the fight for a stable, lasting peace," Shmyhal added. "Ukraine is firmly committed to continuing cooperation. I am confident that support from the U.S. will continue. We are looking for ways for pragmatic cooperation and are ready to sign, including an agreement on minerals."

Allied leaders and officials -- already mobilizing to provide more aid and political backing for Ukraine in response to the Trump administration's skepticism -- also expressed concern over the White House decision.

"We need the Americans militarily," Finnish Foreign Minister Elina Valtonen said during a Chatham House think tank event in London on Tuesday when asked about the aid pause. "On the battlefield, Russia has not really been advancing in recent months," she added. "This definitely shouldn't be a moment where we give in."

Benjamin Haddad, The French minister delegate for Europe, said the pause to U.S. aid "means moving peace further away." He added, "To end the war, pressure must be put on the aggressor, Russia," suggesting European nations must now mobilize to fill the gap left by the U.S.

In Russia, meanwhile, Kremlin spokesperson Dmitry Peskov told journalists, "It is obvious that the U.S. has been the main supplier of this war so far," as quoted by the state-run Tass news agency. "If the U.S. stops being one or suspends supplies, this will probably be the best contribution to the cause of peace," Peskov said.

Two officials familiar with the matter told ABC News that around 90% of the military equipment committed to Ukraine by past Presidential Drawdown Authority packages have already been delivered to the country.

That includes the vast majority of critical munitions and anti-armor systems -- such as Javelin anti-tank weapons -- they said, adding that most of what is still in the pipeline are armored vehicles that take longer to refurbish. Those were expected to be ready for delivery in the coming months, with all PDA equipment previously on track for delivery by August 2025.

A steady flow of arms is still set to move from the U.S. to Ukraine for at least the next several years thanks to contracts Kyiv signed with private American companies for newly produced weapons.

Many -- if not most -- of those contracts have been paid. The Trump administration could still attempt to disrupt those shipments through the use of emergency authorities, but there is currently no indication it is trying to do so.

Exactly what equipment earmarked for Ukraine will now be frozen in place is not clear.

Among former President Joe Biden's final four PDA packages announced in December and January -- collectively worth some $3 billion -- were missiles and support equipment for Ukraine's U.S.-made F-16 fighter jets, rockets for use by American-made HIMARS systems, artillery munitions and surface-to-air missiles for Ukrainian air defense batteries.

The most immediate impacts of the U.S. freeze will on air defense, leaving Ukrainian forces and cities more exposed to Russian drones and missiles, the Ukrainian intelligence official said. There will also be a lack of HIMARS long-range rocket artillery, which Ukraine has no analogue for.

Ukraine will start to experience potentially serious artillery ammunition shortages by mid-summer, they said, which will weaken the defense line. The official said this could even increase the risk of a Russian breakthrough.

The official also warned that the freeze could trigger a political crisis in Ukraine by increasing tensions within the country.

Malcolm Chalmers, the deputy director-general of the Royal United Services Institute think tank in the U.K., told ABC News that recent estimates indicate the U.S. share of all military hardware sent to the front has fallen to around 20%, with 25% coming from Europe and 55% domestically produced in Ukraine.

But the 20% accounted for by the U.S. "is the most lethal and important," Chalmers said. "Ukraine will not collapse -- they already experienced an aid cutoff last year. But the effect will be cumulative."

The Washington-based Institute for the Study of War suggested that the suspension of U.S. aid will encourage Putin "to continue to increase his demands and fuel his conviction that he can achieve total victory through war."

Mykola Bieleskov, an analyst at Ukraine's National Institute for Strategic Studies, told ABC News that Ukraine can keep fighting at the current tempo for six months to a year while Europe and Kyiv try to ramp up production to fill the gap.

A member of Ukraine's parliamentary defense committee, Fedir Venislavskyi, told Ukrainian media that Kyiv has a resilience reserve of about six months -- even without systematic support from the U.S.

Still, Venislavskyi said the situation will be complicated by any freeze in U.S. aid, adding that work is currently underway to find alternative sources of supply for critically important weaponry.

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