On Friday Sri Lanka President Rajapaksa will hold bilateral discussions with the Vietnamese President to explore opportunities to strengthen relations promote co-operation.
The foreign ministry said several agreements on political, defence, investment, finance, education and training, machinery manufacturing will be signed after the discussions.
Later on Friday President Sang will inaugurate a Sri Lanka Vietnam business forum which organized with the Ceylon Chamber of Commerce.
The President will also ceremonially open the newly set up Vietnam embassy in Colombo on Saturday and visit Sri Lanka Jem and Jewelry authority.
President Sang will be coming to Sri Lanka after visiting India.
Vietnam is allowing India to explore off-shore oil in the South China Sea, where tensions has risen in recent months due to aggressive Chinese maritime activity.