Since the dissolution of the USSR, it is widely acknowledged that arms dealers have been buying up massive stockpiles of ex-Soviet weapons and selling them to conflict zones around the world, including to countries subject to EU and UN arms embargoes.

That there is a problem with illegal trade in arms is not in doubt. In June, for example, there were reports that Ukrainian arms had been intercepted in Nigeria on the way to Equatorial Guinea.

To what extent have UK arms brokers been involved and, if they have, have they done so in breach of UK law?

These questions have been raised as a result of a visit to Ukraine by the House of Commons committee on arms export controls.

In May my committee visited Ukraine to discuss and compare our two systems of arms export controls and parliamentary scrutiny of them. As well as being one of the world’s leading arms exporters of newly produced weapons, Ukraine inherited a large stockpile of weapons and ammunition from the former Soviet Union.

We had a fruitful dialogue about the system of licensing arms exports introduced in Ukraine and agreed that this would continue. The following should not be interpreted as a criticism of that country’s arms export control regime, but as an urge to action by the UK.

During our visit we were given a document containing a list of UK-registered brokers to whom the Ukrainian authorities had granted export licences. A subsequent translation into English showed that the end users included countries for which the FCO would not have granted a UK export licence.

I cannot disclose more detail than this because the list is now in the hands of both HMRC and the Export Control Organisation for further investigation. And I am pleased that the foreign secretary has confirmed that this is taking place.

But what did surprise us was that it appears the UK authorities were unaware of the existence of such a list of UK brokers granted licences by Ukraine.

Inevitably there are concerns that UK brokers could be exporting arms to undesirable destinations without the control, or knowledge of, our Export Control Organisation or the FCO.

A number of conclusions follow from this. First, our embassies and diplomatic posts must engage more effectively with the national export control organisations to obtain information on UK arms brokers licensed by other countries.

Second, the government needs to establish a register of UK arms brokers.

We have consistently argued for tighter extra-territorial controls on brokering and trafficking by UK citizens and companies. And, I am pleased to say, the government has progressively extended controls to more and more items on the Military List.

However, the problem of effective enforcement remains, which is why we have called for a register of UK arms brokers and more effective end-use monitoring.

The UK must do yet more to ensure that its arms export industry, and individual UK citizens working overseas, are not engaging in the illegal arms trade.