By Jason Farrell, Senior Political Correspondent

The British army will help in operations to defeat the al Qaeda affiliated terrorist group al Shabaab in Somalia, the Prime Minister is to announce today.

David Cameron has agreed that the UK will deploy a peacekeeping force to Somalia as part of the UN support for the African Union soldiers who are fighting against the extremist group.

The UK troops would provide medical, logistical and engineering support and not be involved in frontline operations.

The UK will also send peacekeepers to South Sudan which has been blighted by a brutal civil war which has seen two million people displaced and millions more facing food shortages.


Al Shabaab fighters in Somalia

British troops will provide engineering work to strengthen infrastructure as well as combat training and advisory support.

Precise numbers have yet to be agreed but up to 70 personnel could be deployed to Somalia and a total of 250-300 troops in South Sudan, over the course of multiple deployments.

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Mr Cameron will pledge the military support at a special summit at the United Nations General Assembly designed to bolster international support for peacekeeping missions across the world.

Speaking to reporters travelling with him, David Cameron said: "First of all these are peacekeepers. Britain has for many many years supported peacekeeping operations and taken part in peacekeeping operations. We think they are extremely important and think that also the quality of peacekeeping forces and what they do needs to be enhanced and Britain has a particular role in training and logistics and expertise and standards and so we want to step up.

"Let me stress that obviously we will want to see all the right force protection arrangements to be in place, but we should be playing a part in this. The outcome is Somalia if it is a good outcome - that's good for Britain. That means less terrorism, less migration, less piracy. Ditto in South Sudan. If we can, as peacekeepers, help to maintain a level of decency to enable development in that country, there will again be less poverty, less migration, less issues that affect us back home.

"So I think it's right we are stepping up to do this role because of the resources we have - but we will take very great care for the security and safety of our troops."

The UK was one of the first peacekeeping nations and currently has around 280 troops participating in the UN mission in Cyprus.

UN Secretary General Ban Ki-moon and President Barack Obama are co-hosting today’s Peacekeeping Event at which more than 45 countries are set to be represented, with many expected to announce peacekeeping contributions.

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