Leading article: An immoral loophole

It is impossible to make a morally-defensible case for cluster bombs. Their scattered "bomblets" are designed to cause damage over the widest possible area. And so many lie unexploded after initial impact that they routinely maim and kill civilians, particularly children drawn to their bright, toy-like colours, long after they have been dropped.

So indiscriminate and inhumane a weapon are these munitions that a global treaty outlawing them, the Convention on Cluster Munitions (CCM), was adopted by 107 countries in 2008.

It is shameful then, that some of Britain's biggest banks, including two which are majority-owned by the taxpayer, may be helping to bankroll companies that manufacture them. That it is possible while we remain signatories to the Convention is a travesty.

Some banks are already unilaterally starting to do the decent thing. HSBC, for example, says it is pulling back from such investments. But leaving the issue to financial institutions' discretion is insufficient. The problem is the legal grey area. While CCM signatories undertake not to use, develop or sell cluster bombs themselves, secondary legislation is needed to ban financial institutions from investing in companies that do. Other countries have dealt with the issue. Belgium, Luxembourg, Ireland and New Zealand have such laws in place. But Britain does not.

Amnesty International is now calling on the Government to institute the necessary laws. It is a campaign that should not have been necessary and deserves the fullest support. In the aftermath of last week's riots, the Prime Minister has talked a great deal about morality. His government should set an example. The current situation makes a mockery of the spirit of the CCM. We have a moral obligation to change it.