The enigmatic batsman also admitted that he had not given enough time to prove his fitness and had no one to blame but himself for not getting a central contract.
"I dont blame anyone, I am to blame for not getting the contract. I am now taking my fitness and training very seriously as I want to get back into the national team stronger and fitter, he said in an interview from London where he has gone to undergo rehabilitation for a knee problem.
He said he had been dragged into the spot-fixing scandal but the PCB has now cleared him of any involvement.
"All my life I have never been involved in such things and I have only wanted to do well for my country," he said.
Umar, who was sent back from England after failing a fitness test before the Champions Trophy and before that was also dropped for the tour to the West Indies on fitness grounds, said he had no grouse with anyone including head coach Mickey Arthur.
Umar also admitted that he really regretted missing out on the Champions Trophy.
"It was hard to accept that I could have been part of this history making team. And I felt bad not being part of the Champions Trophy. But I always wished the players well and hoped they won the tournament," he added.
Umar's last ODI appearance was in Australia in January and he said he had come to London after taking permission from the PCB.
First Published: July 26, 2017, 10:12 PM IST