Talks between the U.S., Ukraine and European officials to discuss ending Russia's war in Ukraine faltered as Secretary of State Marco Rubio abruptly cancelled his trip to London.

Planned diplomatic talks on Wednesday have been scaled back, raising new doubts about progress toward a cease-fire between Russia and Ukraine.

Rubio’s last minute decision to cancel means there will be no foreign ministers’ meeting in London over Ukraine peace talks but Witkoff will still go to Moscow.