A leading group working on behalf of disabled people accused the United States Wednesday of pressuring European and African countries not to join a new treaty next month banning cluster bombs.

"Five weeks before the conclusion of the historic Cluster Munition Treaty, Handicap International urges states to resist the growing pressure from the United States and other arms producing countries," a statement said.

Cluster bombs are notorious for killing and maiming civilians. They contain smaller bomblets, which scatter over a wide area and can explode decades after a conflict has ended.

The treaty banning the weapons, which is opposed by China and Russia, is expected to be published in Dublin during an event involving almost 100 countries from May 19 to 30.

"We got evidence from a number of states they have been lobbied, sometimes very aggressively, by the US," said Stan Brabant, head of the non-governmental organisation's Belgian section.

He said African states had been threatened with losing aid from the United States if they signed up, while some in Europe were told such a ban could hurt the NATO military alliance.

He also accused Britain and the Netherlands -- which have used the munitions in Iraq and Kosovo -- of trying to weaken treaty provisions on helping the victims of such weapons.

Another group of countries was accused of trying to water down the treaty so as to exempt from any ban the cluster munitions that they produce.

No official records exist of how many people have been maimed or killed by the weapons, but Handicap International estimates that about 98 percent of victims were civilians, usually children.

The treaty is part of a Norwegian initiative launched in February 2007 when 46 states agreed to conclude an international ban treaty to be signed by the end of this year.

Cluster munitions are among the weapons that pose the gravest dangers to civilians since antipersonnel mines, which were banned in 1997.

They caused more civilian casualties in Iraq in 2003 and Kosovo in 1999 than any other weapon system. Israel's widespread use of cluster bombs during the 2006 war in Lebanon caused more than 200 civilian casualties in the year following the ceasefire, the Cluster Munitions Coalition has said.