Yemen was accused before the UN on Monday of using anti-personnel mines near its capital, even though it has signed a convention that bans all such weapons, as campaigners demanded an immediate investigation.

Members of the Anti-Personnel Mine Ban Convention, meeting at the UN in Geneva this week, demanded explanations following charges from Human Rights Watch (HRW) and others that Yemen's Republican Guards laid banned anti-personnel mines near Sanaa in 2011.

The head of Yemen's national mine action committee, Ali Mohammed al-Kadri, vowed to "thoroughly investigate" the new allegations and "if need be prosecute and punish those responsible for their use."

The International Campaign to Ban Landmines (ICBL), of which HRW is a member, said it was "deeply disturbed" by the reports, which identified the use of several types of mines that had caused civilian casualties, including children.

If confirmed, it stressed, this would be a serious violation of Yemen's obligations under the Mine Ban Treaty.

According to the organisation, 162 people, including 110 children, were believed to have been killed in Yemen in the first half of 2012 alone by mines or explosive remnants of war.

Yemen was among the first countries to sign the treaty in 1997, agreeing never to use anti-personnel mines under any circumstances.

"It is unconscionable that a state which has signed on to ban these indiscriminate weapons could allow use by government forces," ICBL chief Kasia Derlicka said in a statement.

Yemen said in 2002 it had destroyed all its landmine stockpiles and it had been expected to finish clearing all mines from its territory by 2015.

"The new findings suggest that the previous declaration of stockpile destruction was incorrect or that Yemeni forces have since acquired a new supply of anti-personnel mines, in breach of the Mine Ban Treaty," ICBL said.