Donald Trump and North Korea tipped to be on agenda as Barack Obama renews friendship with Shinzo Abe

Japan’s prime minister Shinzo Abe and US president Donald Trump may be famed for a friendship nurtured over countless games of golf, hamburgers, late night phone calls and complimentary tweets.

But Mr Abe was united with another high-profile “friend” on Sunday: the former US president Barack Obama, who is joined the Japanese PM for lunch in Tokyo.

Mr Obama arrived on Saturday for a two-day trip in order to attend an international conference, marking his first visit to Japan since he left office in January last year.

Confirming the lunch meeting, Yoshihide Suga, chief cabinet secretary, was quick to emphasise their encounter would not be political but would simply provide an opportunity to deepen their friendship.

His comments conflicted with local media reports earlier this month claiming there would be one key topic which the pair were most likely to discuss while catching up over lunch: North Korea.

At the conference on Sunday, Mr Obama said negotiations with North Korea on its nuclear weapons programme were difficult, partly because the country's isolation minimises possible leverage, such as trade and travel sanctions against Pyongyang.

"North Korea is an example of a country that is so far out of the international norms and so disconnected with the rest of the world," Mr Obama told a packed hall in Tokyo, where he was  welcomed by a standing ovation.

He stressed the effort to get North Korea to give up nuclear weapons remains difficult, but countries working together, including China as well as South Korea and Japan, to combine pressure on North Korea will be better than nations working alone.

It’s a timely visit for Mr Abe, who may well be questioning the security of his relationship with Mr Trump, after reportedly feeling sidelined by Seoul’s role in fast-paced diplomatic plans to hold a Pyongyang-Washington summit in May.

At the same time, Mr Abe has also been dealing with plummeting popularity in Japan due to a spiralling cronyism scandal relating to the cut-price sale of state-owned land to a right-wing school operator with ties to the PM’s wife.

Amid such political turbulence, Mr Abe was  no doubt looking forward to enjoying a relaxed lunch with Mr Obama, with whom he appeared to forge an unexpected connection during his time as president.

The friendship that grew between them during Mr Obama’s tenure in power was perhaps not an obvious one at first, bearing in mind the former president’s Democratic allegiances and Mr Abe’s nationalist tendencies.

However, the pair shared a historic series of milestones in bilateral relations, most notably two years ago when Mr Obama became the first sitting US president to visit Hiroshima, the site of the 1945 nuclear bomb attack by American forces.

Meanwhile, Mr Abe joined Mr Obama just months later when in a further show of symbolic unity, they visited Pearl Harbour in Hawaii together, paying tribute to those killed in the Japanese attack in 1941.

The best way to handle a leader such as Mr Trump was one possible topic of conversation that might be tackled by the pair when they met for lunch on Sunday, according to Dr John Nilsson-Wright, senior lecturer in Modern Japanese Studies at Cambridge University and senior fellow of Northeast Asia at Chatham House. 

Describing how Mr Abe appeared to have “lost the ear of the president”, he told the Telegraph: “I imagine that Mr Obama might stress the importance of inter-alliance cooperation and using a collective approach to limit the unilateral instincts of Mr Trump.

“This presumably would involve closer cooperation between Seoul and Tokyo, and possibly reaching out to China - and maybe even Russia - to see if a comprehensive regional security solution might be devised.

“Such a multilateral process clearly will involve difficult coordination challenges, but it will have the merit of slowing the tempo of the steady drumbeat in favour of war that we heard in recent months, but which had been temporarily silenced by the May summit announcement.”

The list of concerns that are currently facing Mr Abe as he lunched with Mr Obama – and can potentially be discussed between the pair - is as long as it is complex.

Dr Nilsson-Wright added: “The twin worries for Mr Abe are likely to be firstly, that a May summit may encourage Mr Trump, in order to get a deal with the North, to make strategic concessions to the North that will undermine Japanese interests.

“A second fear is that a failed summit will ratchet up the pressure for war, increasing the chance that Japan will be dragged into a wider military conflict.”