India is investigating how Swedish-made weapons bought by its army turned up in Myanmar, a minister visiting Yangon said Saturday, denying New Delhi had supplied arms in contravention of EU sanctions.

Sweden asked India on Thursday to clarify how the weapons wound up in Myanmar after it was revealed the Indian army had purchased them, Trade Minister Ewa Bjorling told the Swedish parliament.

Bjorling said the Swedish Agency for Non-Proliferation and Export Controls (ISP) had informed her that the weapons had come from India.

Pictures taken in Myanmar and published in Swedish media this week showed a Carl Gustaf M3 anti-tank rifle and ammunition left behind by Myanmar government soldiers.

The weapon's serial number is clearly visible in one of the photographs.

"One thing is clear... we are not in the business of supplying weaponry," Salman Khurshid, Indian Minister of External Affairs, told reporters in Yangon.

"We will try to find out how this happened. It's one weapon, isn't it? In a very big world, one single weapon has been identified," he said, adding that the Indian army will check its inventory as part of the probe.

The minister has met with Myanmar's President Thein Sein and opposition leader Aung San Suu Kyi during his trip, holding discussions on energy, infrastructure and border issues.

According to a story published in Britain's Independent newspaper, the Swedish weapons were used by Myanmar troops in their fight against ethnic Kachin rebels in the country's far north.

The rebels urged Myanmar's military to end hostile operations in September after fighting broke out last year following the collapse of a 17-year ceasefire between the two sides, forcing tens of thousands of people to flee their homes.

Several rounds of talks aimed at resolving the conflict have been overshadowed by ongoing battles.

The European Union has had a weapons embargo against Myanmar since 1996.

On Wednesday, an ISP spokeswoman said it was "relatively unusual" for Swedish weapons to end up in the hands of third parties.