Myanmar's ruling junta said Friday it had no intention of building an atomic bomb, brushing aside Western concerns about possible nuclear cooperation with North Korea.

The denial came after the United States raised concerns about "growing military ties" following a report that Myanmar had begun a nuclear weapons programme with Pyongyang's help.

In a statement carried by state media, Myanmar's foreign ministry said: "These reports were baseless accusations that are politically motivated.

"Myanmar is a country that always respects UN declarations and decisions as it is a UN member country. Myanmar is not in a position to produce nuclear weapons. Myanmar has no intention to become a nuclear power."

The statement also said recent nuclear allegations were aimed at undermining renewed dialogue between the United States and Myanmar in the run-up to elections later this year.

The allegations aim "to undermine the political process as Myanmar is striving for democracy by holding general elections this year," the statement said.

The comments follow a recent documentary by the Norwegian-based news group Democratic Voice of Burma (DVB) that said Myanmar was trying to build an atomic bomb.

The documentary cited a senior army defector and years of "top secret material". It showed thousands of photos and testimony from defectors that it said revealed the junta's nuclear ambitions and a secret network of underground tunnels, allegedly built with North Korean help.

The years-long investigation included hundreds of files and other evidence from the defector, army major Sai Thein Win, who said he was deputy commander of a military factory that was part of Myanmar's nuclear battalion.

"They really want to build a bomb. That is their main objective," he was quoted as saying.

US Senator Jim Webb cancelled a planned trip to Myanmar last week in response to the allegations, saying it would be "unwise and potentially counter-productive".

The findings "contain new allegations regarding the possibility that the Burmese government has been working in conjunction with North Korea in order to develop a nuclear programme," Webb said.

Myanmar, which has been under military rule since 1962, has been accused of violating a UN Security Council ban on North Korean arms exports imposed last June.

Following a visit there in May, US Assistant Secretary of State for East Asian and Pacific Affairs Kurt Campbell expressed concern about a suspected arms shipment from North Korea to Myanmar.

President Barack Obama's administration last year launched a dialogue with Myanmar's military rulers, after concluding that attempts to isolate the regime had met with little success.

But Washington has sharply criticised preparations for this year's elections -- the first in 20 years -- as well as raising the nuclear concerns.

Myanmar severed ties with Pyongyang in 1983 following a failed assassination attempt by North Korean agents on then-South Korean president Chun Doo-Hwan while he was visiting the Southeast Asian nation. The attempt left 21 people dead.

But with both countries branded "outposts of tyranny" by the United States they have tried rebuilding relations in recent years.

Myanmar is preparing for rare elections later this year that critics have dismissed as a sham due to laws that have effectively barred opposition leader Aung San Suu Kyi from participating.