Kyiv is working with allies on security guarantees akin to NATO's mutual protection pledge, Ukraine's president Volodymr Zelensky has said. Officials from Ukraine and allies the U.S., the U.K., France and Germany met in London on Thursday in a week when a peace proposal was produced which outlined an Article 5-like agreement which would be backed by Washington.

Despite negotiations to end the war in Ukraine hitting a wall and a deadly Russian strike on the country's capital city early Thursday, President Donald Trump remained insistent that talks had made "a lot of progress.