Amir, who took 17 wickets at the recent World Cup, will continue to play one-day and Twenty20 international cricket.

After making his Test debut aged 17 against Sri Lanka in 2009, he was one of three Pakistan players jailed for a plot to bowl deliberate no-balls in a Test against England in 2010.

He returned to Test cricket in 2016 after a five-year ban for spot-fixing.

"It has been an honour to represent Pakistan in the pinnacle and traditional format of the game but I have decided to move away from the longer version so I can concentrate on white-ball cricket," he said.

"Playing for Pakistan remains my ultimate desire and objective, and I will try my best to be in the best physical shape to contribute in the team's upcoming challenges, including next year's T20 World Cup.

"With the World Test Championship commencing shortly, and Pakistan boasting some very exciting young fast bowlers, it is appropriate that I call time in Test cricket so that the selectors can plan accordingly."

Amir played 36 Tests, taking 119 wickets at an average of 30.47, with a best of 6-44 against West Indies in Kingston in 2017.

Between his debut in Galle and the start of his ban for his role in the spot-fixing scandal at Lord's, Amir played 14 Tests, claiming 51 wickets at an average of 29.09.

Since making his return to Test cricket, also against England at Lord's, Amir took 68 wickets in 22 Tests at an average of 31.51, his final match coming against South Africa in January.

"Amir overcame adversity as a young cricketer and came back stronger not only as a cricketer but also as a better human being," said Pakistan Cricket Board managing director Wasim Khan.

"His skill, on the field, and his personality will be missed in the dressing room in the longer format.

"However, we respect his decision and look forward to him continuing to play an integral role in white ball cricket for Pakistan."

Amir has played 77 one-day internationals and 42 Twenty20s for Pakistan and will play for Essex in this summer's T20 Blast campaign.

He was left out of Pakistan's provisional World Cup squad after a poor run of form following the 2017 Champions Cup victory.

But he had an impressive tournament after being recalled to the final 15-man squad, taking 17 wickets in eight matches at an average of 21.05.