Myanmar is not wealthy enough to acquire nuclear weapons, a top government official told visiting US Senator John McCain, who called Friday for an end to any military ties with North Korea.

"Myanmar is no position to take account of nuclear weapons and does not have enough economic strength to do so," state media quoted Vice President Tin Aung Myint Oo as telling McCain in talks in the capital Naypyidaw on Wednesday.

He said Myanmar was abiding by UN resolutions and has halted a peaceful nuclear research programme supported by Russia because the world "may misunderstand," according to the New Light of Myanmar English-language daily.

McCain was in Myanmar to assess the new political landscape after the junta handed power to a nominally civilian government in March.

"The new government must abide by its international obligations to uphold United Nations Security Council resolutions regarding non-proliferation, and to cease any military cooperation with the government of North Korea, as required by international law," he said Friday at the end of the three-day visit.

US diplomatic memos released last year by the website WikiLeaks said Washington has suspected for years that Myanmar ran a secret nuclear programme supported by Pyongyang.

A UN report released in November said North Korea was supplying banned nuclear and ballistic equipment to Myanmar, along with Iran and Syria.

A documentary last year by the Norwegian-based news group Democratic Voice of Burma said Myanmar was trying to develop nuclear weapons, citing a senior army defector and years of "top secret material".