Up to 70 soldiers will join a United Nations contingent supporting African Union troops fighting Al Shabab in Somalia, whose militants have been fighting against Somalian government to take the control of the country.
Another 300 will also be deployed to South Sudan over time. Those being sent to South Sudan will help combat training missions as well as engineering assignments.
British Prime Minister David Cameron thinks that move will be able to restrain migrants coming to Europe.
People from Somalia, including with Syria, Iraq, Afghanistan and Eritrea comprise two thirds of migrants making long and dangerous journeys across the Mediterranean to reach Europe.
"The outcome in Somalia, if it's a good outcome, that's good for Britain. It means less terrorism, less migration, less piracy. Ditto in South Sudan: if we can, as peacekeepers, help to maintain order and peace and see stable development in that country then that is going to be, again, less poverty, less migration, less issues that affect us back at home" said Cameron.
PM Cameron added that British troops will not be involved in combat roles.
"It's not committing troops to conflict, it's committing troops to a UN blue-hatted peacekeeping role - as we've done many times in the past, as we will do in the future,"
British forces deployed in the region will also provide combat training and medical, logistical and engineering support.
"And one of the reasons we're doing it is obviously the expertise that British troops have in training, engineering, and mentoring and we're raising the standard for peacekeeping troops which has had some issues and problems in the recent past."