has stepped aside from Bangladesh's T20 World Cup squad, explaining that he did not want to take the place of openers who have been playing in the format more regularly than him in recent times.
Tamim informed the BCB president Nazmul Hassan and chief selector Minhajul Abedin of his decision on Wednesday, prior to making the announcement from his official Facebook page.
Tamim, however, made it clear that he was not retiring from T20Is, but given his lack of involvement in the T20 World Cup build-up, he felt it would be unfair to take the place of those players who had been tried in his stead.
Soumya Sarkar and Mohammad Naim opened mostly in Tamim's absence, while Liton Das and Mahedi Hasan are the other two candidates who could potentially take those spots. Bangladesh haven't announced their T20 World Cup team yet, but all four are likely to be in the squad.
Tamim said that he would have been fit in time for the but the lack of T20s also played a part in his decision making.
"A little while ago I called our board president and chief selector," he said. "I want to share the same with you. I told them that I don't think I should be in the World Cup team. There are a few reasons why I am not available for the tournament. Game time is the biggest reason. I haven't been playing this format for a long time.
"I don't think my knee injury is a concern, because I was going to recover before the World Cup. The main reason that clicked with me when taking this decision was, I don't think it would be fair on those players who have played in the last 15-16 T20Is that I haven't played. I was probably going to be in the World Cup team, but I believe it wouldn't have been fair on those players."
Tamim was a regular in the Bangladesh T20I side until he pulled out of the New Zealand series in March this year. It raised speculation that he was about to retire from the format but Tamim later hinted
that playing all three formats wasn't "ideal" at this stage of his career. He also missed the T20Is against Zimbabwe and Australia due to a knee injury.
Chief selector Abedin had recently said to the media that he expected Tamim to walk in to the T20 World Cup side, although coach Russell Domingo had avoided answering a question about the player during a Zoom press conference on Monday.
Tamim, however, stressed on the fact that this wasn't a retirement, but skipping a tournament for which there are better prepared openers. "I want to make it clear that I am not retiring but I won't be playing this World Cup. I think it is a fair decision.
"Those youngsters who are playing in the national team, they should get the opportunities. Their preparation will be better than mine. They will probably be able to serve the team better."
Tamim said that he will look for playing opportunities before Bangladesh's next assignment, after the T20 World Cup, but asked the media to respect his decision and privacy.
"I would ask the media not to call or message me on Whatsapp. I have taken this decision, and I will stick to it. I have given you all the reasons. I am hopeful that you will respect my privacy and the decision. There's no controversy.
"This is what I felt. Those who are close to me, know that whatever I do, I do it from the heart. My heart told me this was the right decision. I think it is the best for the team. I will try to keep myself busy with any format during this time," he said.
Tamim has played 74 T20Is for Bangladesh, having recently lost his place as the highest scorer in the format with Shakib Al Hasan taking his place. He has also scored the only century for Bangladesh, apart from his eight fifties.
Mohammad Isam is ESPNcricinfo's Bangladesh correspondent. @isam84