U.K. Prime Minister Keir Starmer proposed a peace plan for Ukraine and Russia on Sunday, alongside French President Macron and other European leaders, during a meeting with Ukrainian President Zelenskyy.

The plan calls for European countries to take on more responsibility for Ukraine’s security in exchange for a peace agreement, with the U.K. ready to deploy troops and air force assets.

However, Starmer acknowledged the plan’s reliance on U.S. support. Macron outlined a 30-day freeze on strikes to facilitate negotiations.

Zelenskyy emphasized Ukraine’s strength as its best security guarantee, while U.S. Secretary of State Marco Rubio said security guarantees could only come after peace talks, Fox News has reported.

Tensions between Zelenskyy and U.S. officials grew following a heated White House meeting, with some Republican senators, like Lindsey Graham, calling for Zelenskyy’s resignation.

Written by B.C. Begley