Theresa May and Shinzo Abe have agreed to maintain pressure on North Korea following the Japanese Prime Minister's re-election.
The two leaders vowed to continue working with the international community to tackle Kim Jong Un's "destabilising activity".
Mr Abe secured a decisive victory in a snap election - unlike Mrs May, who lost her Commons majority when a similar electoral gamble backfired in June.
A Downing Street spokesman said: "This morning the Prime Minister called Prime Minister Shinzo Abe of Japan to congratulate him on his success in the Japanese general election.
"The Prime Minister and Prime Minister Abe discussed North Korea and agreed to continue to work with the international community to maintain pressure on the regime to cease its destabilising activity. They noted the role the UK played in the EU agreeing tough sanctions on North Korea last week.
"The leaders reflected on the Prime Minister's successful visit to Japan in August and the positive impact it has had on UK-Japan relations. They looked forward to deepening ties between our two countries on trade, security and defence.
"The Prime Minister also offered Prime Minister Abe her condolences on the impact and loss of life caused by Typhoon Lan."