The decision was taken during a UNP Working Committee meeting at the party headquarters - Sirikotha this morning (08).
The WC meeting, which is the first since the 2015 January Presidential election, was held under the auspices of the UNP leader Ranil Wickremesinghe.
Mr. Samarawickrama, who held this post in the past as well, played a prominent role as the main coordinator of discussions between Wickremesinghe and Chandrika Bandaranaike Kumaratunga, which focused on fielding a common candidate at the 2015 January Presidential election.