On Tuesday morning local time, North Korea launched a missile that passed over the northern Japanese island of Hokkaido, which Prime Minister Abe labelled "an unprecedented, grave, and serious threat" to regional security.
On a visit to Japan, May also said Britain and the European Union must focus on their future relationship, "ensuring we can get that trade deal right and also that we can form new trade deals around the rest of the world".More news: Trump says he wants to 'bring back Main Street'
Tokyo and London also pledged to work with the worldwide community to strictly implement the United Nations Security Council's sanctions on North Korea with a view to bring about its denuclearization, according to the statement. The Council, which was created at the end of 2013, consists of Prime Minister Shinzo Abe and key ministers.
May, who told reporters on her flight to Japan that China was "the key" in exerting pressure on North Korea to curb its missile programme, told the BBC she was "pleased that there was a united condemnation" of North Korea from the United Nations security council late on Tuesday.
"We will set up a new joint working group to examine how we can unblock remaining barriers to trade and take steps to build the closest, freest trading relationship between the United Kingdom and Japan after Brexit".More news: Mumbai Rains: Missing doctor confirmed dead as body found at Worli
Britain and Japan will work "quickly" to establish a new economic partnership post-Brexit, Theresa May has said.
"The close cooperation between our two countries is particularly important in this critical juncture, with North Korean provocations presenting an unprecedented threat to worldwide security", May said at a press conference. On Thursday, May will visit a Japanese warship and address the country's national security council as well as the trade event, before seeing Akihito on Friday. "What Japanese businesses and other businesses have asked us to look at is this issue of the certainty going forward of not having a cliff edge". May arrived in Japan Wednesday with an eye to soothing Brexit fears and pushing ahead on early free-trade talks with the world's number three economy.More news: Here's Where We Are With the President's Transgender Military Ban