More than 150 financial institutions worldwide invested around $27bn in companies producing cluster munitions in spite of an international ban, says a report from the Netherlands-based peace organization PAX.

According to the Guardian, the document lists in its “hall of shame” banks, pension funds and other financial institutions that have contributed to production of the munitions between June 2011 and September 2014.

Most of the investors are from the U.S. (76), South Korea (22) and China (21), but there are also three from Germany and seven from the UK. One of the biggest investors is a Singapore-based company.

Cluster munitions were banned in a 2008 Oslo convention that came into force in 2010 and has been signed by 115 countries. The convention followed years of campaigning against the weapon, which kills a disproportionate number of civilians, particularly children.

Among countries still to sign the convention are the U.S., China and Russia. The U.S. insists that the weapon is legal.

Cluster bomblets dropped from the air are intended to disperse over a wide area. While many explode on contact with the ground, many others do not, remaining dangerous for years after they have fallen. Children in war zones frequently fall victim, some just by accidentally treading on them and others by playing with them, attracted by the bright colors or the prospect of setting off an explosion.

Manufacture continues in those countries that are not party to the convention.

One of the loopholes in the convention is that while production of cluster munitions is banned, it is not illegal to invest in companies that produce them.

The report calls for all 151 financial institutions in the “hall of shame” to develop policies that exclude all financial links with companies involved in the production of cluster munitions.

Suzanne Oosterwijk, co-author of the report, said: “Cluster munitions are banned by international law. A majority of the countries in the world have recognized that this weapon is unacceptable. And yet cluster munition producers are still able to fund their activities. Financial institutions should introduce robust policies to ensure they are not supporting companies involved in the production of this banned weapon.”

Echoing this, Amy Little, campaign manager at the Cluster Munition Coalition, said: “We must put lives before profit. We’re talking about a weapon that is currently killing civilians in Syria and eastern Ukraine.”

She criticized investments by companies in countries that have signed the convention. “The UK, Australia, Canada, France, Germany, Japan, Spain and other countries that have joined the global ban on cluster munitions should legislate quickly to ensure they are not supporting the overseas production of weapons they have already outlawed,” Little said.

Several countries, including Ireland, Italy, Belgium, the Netherlands, New Zealand and Switzerland, have prohibited public or private financial institutions from investing in cluster munitions.

The campaign has been successful in persuading some companies previously in the “hall of shame” to end their involvement in the manufacture of cluster munitions.

The convention banning them came after a similar campaign led to a convention on landmines in 1997.