Some 100 nations began putting their names on Wednesday to a landmark treaty banning cluster bombs, amid calls for major arms producers such as China, Russia and the United States to join them.

Norway — which played a key role in hammering out the worldwide ban on using, producing, transferring and stockpiling of cluster munitions — was the first country to sign the Convention on Cluster Munitions (CCM).

"The world is a safer place today," Richard Moyes of the Cluster Munitions Coalition, an umbrella group that comprises some 300 non-governmental organisations, told AFP.

"This is the biggest humanitarian treaty of the last decade."

Dropped from warplanes or fired from artillery guns, cluster bombs explode in mid-air to randomly scatter hundreds of bomblets, which can be just eight centimetres big.

Many bomblets fail to explode, littering war zones with de facto landmines that can kill and maim long after a conflict ends.

Many victims are children

Worldwide, about 100 000 people have been killed or maimed by cluster bombs since 1965, 98 percent of them civilians, says Handicap International, a campaign group.

More than a quarter of the victims are children who mistaken the bomblets for toys or tin cans.

Laos, the country most affected by cluster bombs, was the second to sign Wednesday's treaty at Oslo city hall.

Between 1964 and 1973, the US Air Force dropped 260 million cluster bombs on Laos, or the equivalent of a fully-loaded B-52 bomber's payload dropped every eight minutes for nine years.

Over two days, around 100 countries — including Britain, Canada, France and Germany — are to sign the treaty that was finalised in Dublin in May.

But the world's biggest producers and users of cluster bombs — including China, India, Israel, Pakistan, Russia and the United States — object to the ban and refuse to sign it.

US opposition

Washington reiterated its opposition on Tuesday.

"Although we share the humanitarian concerns of states signing the CCM, we will not be joining them," the US State Department said in a statement when asked for its views on the Oslo signing ceremony.

"The CCM constitutes a ban on most types of cluster munitions; such a general ban on cluster munitions will put the lives of our military men and women, and those of our coalition partners, at risk."

Despite the absence of key countries, opponents of cluster bombs say the treaty — also known as the Oslo Convention — should help stigmatise the use of such weapons even by non-signatory countries.

"The treaty places moral obligations on all states not to use cluster munitions," Norwegian Prime Minister Jens Stoltenberg said.

The Cluster Munitions Coalition shared in his optimism.

"The treaty will increase the political cost of using these weapons for any country," Moyes said. "Even countries that don't sign will struggle to use these weapons in the future."

The group is hopeful that the US position will shift once president-elect Barack Obama moves into the White House on 20 January.

In 2006, Obama voted in the US Senate to ban the use of cluster munitions in heavily populated areas, but in the end the motion was rejected.

AFP