KYIV, Ukraine (AP) — Senior military officers from more than two dozen countries across Europe and beyond met in England Thursday to flesh out plans for an international peacekeeping force for Ukraine as details of a partial ceasefire are worked out.

U.K. Prime Minister Keir Starmer said he didn’t know whether there would be a peace deal in the Russia-Ukraine war, but “we are making steps in the right direction” as a “coalition of the willing” led by Britain and France moves into an “operational phase.”

“We hope there will be a deal but what I do know is if there is a deal, the time for planning is now,” he said during a visit to the meeting of military planners at a British base in Northwood, just outside London. “It’s not after a deal is reached.”

“It is vitally important we do that work, because we know one thing for certain which is a deal without anything behind it is something that (Russian President Vladimir) Putin will breach,” he said.

Ukraine and Russia agreed in principle Wednesday to a limited ceasefire after President Donald Trump spoke with the countries’ leaders this week, though it remained to be seen when it might take effect.

Ukrainian President Volodymyr Zelenskyy, speaking in Norway on Thursday, said that although he originally had sought a broader ceasefire, he was committed to working with the U.S. to stop arms being directed at power production and civilian facilities.

“I raised this issue with President Trump and said that our side would identify what we consider to be civilian infrastructure,” Zelenskyy said. “I don’t want there to be any misunderstanding about what the sides are agreeing on.”

The tentative deal to partially rein in the three-year war came after Putin rebuffed Trump’s push for a full 30-day ceasefire.

Negotiators from Moscow and the U.S. will meet Monday in Riyadh, Saudi Arabia, Putin’s foreign affairs adviser Sergei Ushakov told Russian news agencies.

Zelenskyy said team would also meet with the U.S. in Saudi Arabia to discuss technical issues, and then the U.S. will act as an intermediary running “shuttle diplomacy” between Kyiv and Moscow.

Despite the negotiations, hundreds of drone attacks were launched overnight by both sides, injuring several people and damaging buildings.

Ukraine said Russia had launched 171 long-range drones and it shot down 75. Russia said it destroyed 132 Ukrainian drones in six Russian regions and the annexed Crimea.

More than 50 Ukrainian drones targeted Engels, an industrial city near Russia’s main base for nuclear-capable strategic bombers.

Britain's Prime Minister Keir Starmer speaks as he visits a military base to meet planners mapping out next steps in the Coalition of the Willing in Greater London, Thursday, March 20, 2025.(AP Photo/Alastair Grant, Pool)

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Britain's Prime Minister Keir Starmer speaks as he visits a military base to meet planners mapping out next steps in the Coalition of the Willing in Northwood, London, Thursday, March 20, 2025.(AP Photo/Alastair Grant, Pool)

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Britain's Prime Minister Keir Starmer speaks to a Canadian Lt Colonel as he visits a military base to meet planners mapping out next steps in the Coalition of the Willing in Northwood, London, Thursday, March 20, 2025.(AP Photo/Alastair Grant, Pool)

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Credit: AP