Japan and Britain are expected to agree to a major new defense pact in December, a report said Sunday, as the two countries look to boost cooperation with mutual ally the U.S. amid concerns over China’s growing assertiveness.

The report comes after the two countries' leaders strongly hinted that such a move was in the cards during their first talks days earlier.

Prime Ministers Fumio Kishida and Rishi Sunak spoke over the phone Friday, with the new British leader stating his intention “to forge an even closer bilateral relationship” with Japan, including an understanding “to accelerate the consultation toward an early signature of a Reciprocal Access Agreement,” according to the Japanese Foreign Ministry.