Tehran, Dec 16, 2019 (AFP) -

Iran's President Hassan Rouhani is finalizing with Japan a visit to Tokyo, officials in Tehran said Monday, in what will be the first such trip in two decades.

The trip would likely take place around December 20, after Rouhani visits Malaysia for a Muslim leaders summit in Kuala Lumpur, Japanese and Iranian media reported.

"This trip (to Japan) is being finalized," Iranian foreign ministry spokesman Abbas Mousavi told a press conference in Tehran.

Iranian government spokesman Ali Rabiei said discussions would focus on "expanding economic relations" between the two countries.

"Mr Rouhani's trip to Japan has nothing to do with issues such as negotiations with America," Rabiei said.

"However, our Japanese friends usually convey messages or initiatives, which we welcome... and seriously examine," he added, stressing the bilateral focus of the visit.

Rouhani would be the first Iranian president to visit Japan since 2000.

He is expected to meet Prime Minister Shinzo Abe, who traveled to Tehran in June to try to ease tension between the United States and Iran in the Gulf.

"After Mr Abe's trip to Iran it was natural for the president of the Islamic Republic of Iran to have a trip to Japan," Mousavi said.

Talks between the two leaders would focus on "issues and developments in our region, the East Asia region," and the landmark 2015 Iran nuclear deal, Mousavi added.

On December 9, Abe said he was weighing inviting Rouhani for a state visit.

Noting Japan's alliance with the United States and Tokyo's "favorable relations" with Tehran, Abe said he would make efforts "as much as possible to help ease tensions" in the Middle East.

Japan was formerly a major buyer of Iranian crude but stopped purchases to comply with US sanctions imposed after the United States unilaterally quit the nuclear deal in May 2018.