British Prime Minister Theresa May shakes hands with her Japanese counterpart Shinzo Abe following their joint press conference at the state guest house in Tokyo, Japan August 31, 2017.

TOKYO (Reuters) - Britain and Japan discussed the possibility of adopting a new U.N. Security Council resolution over North Korea, a British government source said on Thursday, after North Korea fired a missile over Japan this week.

The 15-member U.N. Security Council on Tuesday condemned the firing of an intermediate range ballistic missile over Japan as “outrageous” and demanded that North Korea halt its weapons program, but the U.S.-drafted statement did not threaten new sanctions.

“Talks (were) about working together more and things like perhaps adopting a new resolution at UNSC (Security Council), perhaps stepping up sanctions,” the source said, referring to discussions between the prime ministers of Japan and Britain on Thursday.

The source added the leaders wanted to increase the effectiveness of the current sanctions by helping others to implement them.