US President, Joe Biden congratulates new British PM Sunak

US President Joe Biden congratulated new British Prime Minister Rishi Sunak and said they would continue to partner on supporting Ukraine's fight against Russia.

"Congratulations to Rishi Sunak on becoming Prime Minister of the United Kingdom. Together, I look forward to enhancing our cooperation on issues critical to global security and prosperity, including continuing our strong support for Ukraine," Biden said in a tweet.

On Monday Biden described the naming of Britain's first non-white prime minister as "pretty astounding, a groundbreaking milestone." Britain has been a key European ally of the United States in arming and supporting the Ukrainian military as it tries to repel the Russian invasion, which began last February.