WASHINGTON, DC – President Biden is hoping the pond Sunday to talk about the ongoing war in Ukraine and the environment with the UK’s King Charles III and United Kingdom Prime Minister Rishi Sunak.

Biden leaves his Rehoboth Beach, Del. home for London on Sunday, visiting with the UK leaders Monday before heading to Lithuania for the NATO leadership summit on Tuesday and Wednesday.

During the stopover, he will visit Sunak at 10 Downing St. “to consult of a range of bilateral and global issues,” White House Press Secretary Karine Jean-Pierre said Friday.

Those issues are believed to include the nation’s ongoing support for Ukraine, as the nations are among the strongest supporters of Kyiv in the West.

Though the US has spent the most money supporting Ukraine – more than $40 billion in weapons alone – the UK has recently taken on a greater leadership role in the effort.

The UK has been supportive of international efforts to supply Ukraine with American-made F-16 fighter jets, nudging their US partners to green-light pilot training and more.

However, Biden may face awkward conversations with Sunak regarding the president’s Friday decision to send highly lethal – and controversial – cluster munitions to Ukraine.

The prime minister as recently as Saturday said that the UK “discourages their use.”

Next, Biden will visit King Charles at Windsor Castle to “engage with a forum that will focus on mobilizing climate finance – especially bringing private finance off the sidelines – for clean energy deployment and adaptation in developing countries,” Jean-Pierre said Friday.

It will be the first time Biden has met with the king since he was coronated in May. Biden skipped the pomp-and-circumstance ceremony, sending first lady Jill Biden and one of their granddaughters in his place.

Finally, he will continue on to the main event of his trip, attending the NATO summit during which leaders of the allied nations are expected to discuss the potential of accepting Ukraine into the Western alliance – something Russian President Vladimir Putin used as one of his reasons for starting its war on Feb. 24, 2022.

It has been 15 years since NATO leaders in 2008 said Ukraine could eventually become a member, but the alliance has stayed largely mum on the topic in the years since, as the accession of the country that shares so much of its northern, eastern and southeastern border with Russia.

Biden told CNN Sunday that he does not believe Ukraine should join the organization until the Russian invasion is over.

“I don’t think there is unanimity in NATO about whether or not to bring Ukraine into the NATO family now, at this moment, in the middle of a war,” Biden said.

“For example, if you did that, then, you know – and I mean what I say – we’re determined to commit every inch of territory that is NATO territory. It’s a commitment that we’ve all made no matter what. If the war is going on, then we’re all in war. We’re at war with Russia, if that were the case.”

Ukraine President Volodymyr Zelenskyy remains committed to the cause, refusing to cower to Putin’s demands that Kyiv abandon all efforts to join the security alliance.

“I think we have to lay out a rational path for Ukraine to be able to qualify to be able to get into NATO,” Biden told the network.

“But I think it’s premature to say, to call for a vote, you know, in now, because there’s other qualifications that need to be met, including democratization and some of those issues.”