The 36-year-old right hander, in a letter to the SLC, has informed his decision and was scheduled to meet the national selectors later this evening.
Sources close to the batsman said he was disheartened by the treatment meted out to him when he was originally axed from the 20-member squad chosen for the upcoming home Test series against Bangladesh. He was later included in the squad to replace former captain Mahela Jayawardene, who was going to miss the series through injury.
However, he was dropped on Monday from the final 16-member squad, which was announced for the first Test against Bangladesh, starting on Friday in Galle.
A veteran of 81 Tests, Samaraweera has amassed 5462 runs at an average of 48.76 and it includes 14 centuries. Samaraweera, who is considered a highly dependable middle order batsman, is all set to play for Worcestershire in this summer's English county championship.
Samaraweera, who made his Test debut against India in 2001 in Colombo, was among the players who signed the contract with the Sri Lanka Cricket board this week.
The Cricket board has said that has requested Thilan to talk with the national selectors prior to finalising his decision.
Spotted: Virat Kohli, Anushka Sharma and other celebs at Mumbai airport
Photos: Salman Khan's 'special friend' Iulia Vantur at a song launch
Photos: Hrithik Roshan, Anushka Sharma, other celebs dazzle at event
In Pictures: Sex scandals involving Indian politicians
Photos: Abhishek Bachchan and Farah Khan at Boman Irani's birthday bash