Video report by ITV News Political Correspondent Carl Dinnen
Britain and Japan will work "quickly" to establish a new economic partnership post-Brexit, Theresa May has said.
The Prime Minister said the two countries wanted to see a "swift conclusion of the ambitious EU-Japan economic partnership agreement", and that the UK would be free to sign new bilateral trade agreements in any interim period after Brexit.
Japan's Prime Minister Shinzo Abe said new investment by Japanese companies in the UK showed the "profound trust" the companies have in the British economy.
However, Japan's corporate sector had raised concerns about the UK's decision to sever ties with Brussels, while the government previously made clear it wanted the country to remain in the bloc.
Speaking at a press conference in Tokyo during her visit to Japan, Mrs May said: "Announced earlier this month, our intention is that the UK will be free to sign new bilateral trade agreements with partners around the world in any interim Brexit period, and we have agreed here today that we want to see a swift conclusion of the ambitious EU-Japan economic partnership agreement.
"Prime Minister Abe and I have agreed that as we exit the EU we will work quickly to establish a new economic partnership between Japan and the UK, based on the final terms of that agreement.
"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 UK and Japan after Brexit."
Speaking through a translator, Mr Abe said: "The fact that, after the decision on Brexit, Japanese companies are continuing to make new investment into the United Kingdom ... shows the profound trust that Japanese companies have toward the British economy.
"It is important for the world economy to realise Brexit from the EU which is smooth and successful.
"With this in mind I have asked Prime Minister May for her continued consideration for ensuring transparency and predictability so as to minimise its impact on the business activities, including the Japanese companies...
"We also agreed to have further enhancement of the dialogue between the two nations for the strengthening of the bilateral economic relations after the Brexit."
Earlier, Mr Abe told business leaders in Tokyo that he had "trust" in the UK economy after Brexit and the country would remain a "compelling place".
While Mrs May told the business group that Japan was one of the key trading opportunities once the UK has left the EU.
"This is a formative period in shaping the future of my country and as we leave the European Union, so I am determined that we will seize the opportunity to become an ever more outward-looking, global Britain, deepening our trade relations with old friends and new allies around the world," Mrs May said.
She continued: "And there are few places where the opportunities of doing so are greater than Japan, the third largest economy in the world."
However Liberal Democrat Chief Whip Alistair Carmichael criticised the announcement, saying that Mrs May went to Japan seeking a new trade deal but instead had to admit the "biggest priority will be completing the one the EU is already negotiating...
"Once again the promises of the Brexiteers have been dashed on the rocks of reality.
"It's a sign of the Prime Minister's weakness that rather than going abroad to fight for British jobs, she's been forced to desperately fight for her own."
Also at the joint press conference Mrs May insisted she will "get on with the job" of being Prime Minister at a "really critical time in the UK".
The comments came just hours after she revealed she intends to stay on as Prime Minister to fight the next election.
Speaking to ITV News while visiting Japan, Mrs May repeated that she is "not a quitter."