European and US leaders are holding a snap summit in Washington on Ukrainian security and borders, amid concern US president Donald Trump has flipped back toward Russia.
Ukrainian president Volodomyr Zelenskyy will first meet US president Donald Trump at 1.15PM alone in the White House on Monday (18 August), following Trump's landmark meeting with Russian president Vladimir Putin in Alaska on Friday.
Trump has flip-floped toward and away from Russia several times in the past seven months of his second term.
He infamously berated Zelenskyy in the Oval Office in February, but later befriended him in a meeting at the Vatican, before recently threatening Russia with sanctions if it did not agree a ceasefire.
But in his latest U-turn, Trump dropped all that in Alaska and instead agreed to Putin's idea that Ukraine should first give up territories in the Donbas region and Crimea.
Trump also took Putin's side in social media posts on Sunday by painting Ukraine as the aggressor.
"President Zelenskyy of Ukraine can end the war with Russia almost immediately, if he wants to, or he can continue to fight", Trump said.
It remains to be seen how the Zelenskyy-Trump tete-a-tete goes this time round.
But they will be joined by the British, Finnish, French, German, and Italian leaders, as well as the EU Commission and Nato heads, for a working lunch at 3PM.
"It's important for the Europeans to be there: [Trump] respects them, he behaves differently in their presence," Ukrainian MP Oleksandr Merezhko told Reuters.
And for his part, US secretary of state Marco Rubio was more reassuring than Trump anyway.
"They [EU leaders] are not coming here tomorrow to keep Zelenskyy from being bullied. They're coming here tomorrow because we've been working with the Europeans. We invited them to come", he told the CBS broadcaster on Sunday.
Rubio and Trump's Russia envoy, Steve Witkoff, also said the US would play a military role in keeping Ukraine safe from Russia in future — in what would be a major breakthrough for Western allies.
"It would be a very big move by the president, if he were to offer a US commitment to a security guarantee. It tells you how badly he wants peace, how much he values peace, that he would be willing to make a concession like that," Rubio told the Fox broadcaster on Sunday.
"Ukraine has a right, like every sovereign country, to enter into security alliances and agreements with other countries," he said.
Witkoff told the CNN broadcaster of Friday's Alaska summit: "We were able to win the following concession [from Putin], that the United States could offer Article V-like protection ... which was the first time we had ever heard the Russians agree to that".
Article V is the Nato allies' treaty pledge to fight together if one of them was attacked.
But for his part, Zelenskyy sounded cautious despite Witkoff's optimism.
"Putin has many demands, but we do not know all of them ... It's impossible to do this [negotiate] under the pressure of [Russian] weapons," Zelenskyy said, while in Brussels on Sunday.
Aside from annexing five Ukrainian regions, Putin has also previously called for Ukraine to disarm and stay out of Nato, for an end to Western sanctions, and for Nato forces in Europe to pull back to Cold War-era lines, in return for peace.
"There are no details how it [the security guarantee] will work and what America's role will be, what Europe's role will be," Zelenskyy also said.
This year, we turn 25 and are looking for 2,500 new supporting members to take their stake in EU democracy. A functioning EU relies on a well-informed public – you.
Andrew Rettman is EUobserver's foreign editor, writing about foreign and security issues since 2005. He is Polish, but grew up in the UK, and lives in Brussels. He has also written for The Guardian, The Times of London, and Intelligence Online.
Andrew Rettman is EUobserver's foreign editor, writing about foreign and security issues since 2005. He is Polish, but grew up in the UK, and lives in Brussels. He has also written for The Guardian, The Times of London, and Intelligence Online.