Kevin Pietersen has said he "wants to commit to all forms of cricket for England" in a video interview.
The England batsman retired from the limited-overs forms of the game in June and there was speculation next week's third Test against South Africa at Lord's would be his last, after a controversial press conference he gave following the conclusion of the second match of the series at Headingley.
However, when asked during an interview posted on the internet whether he would return unconditionally to the fold, Pietersen said: "I want to commit to all forms of cricket for England, because I love playing cricket for England."
Pietersen wanted to continue playing Twenty20 cricket and retire from one-day internationals but the England and Wales Cricket Board were insistent that he should play in both short forms of the game or none.
His U-turn has now opened the door for his selection in England's defence of the World Twenty20, which gets under way in Sri Lanka next month.
"(I'll play in the) one-day internationals against South Africa in a couple of weeks, the T20 World Cup hopefully if they select me for the squad," he said.
"The selection policy is with the selectors, but yes, I want to make myself available for every single form of cricket for England."
That is in stark contrast to his comments on Monday. "I can't rule out that my next Test may be my last," he said after winning the man of the match award in the drawn second Test at Headingley, after a superb innings of 149 and three wickets.
Pietersen has also had a change of heart about playing a full season in the Indian Premier League.
Pietersen had wanted to miss the Test series with New Zealand next spring to play for Delhi Daredevils.
But when he was asked if he still wanted to play the full season in the IPL, Pietersen said: "Absolutely not, I've taken that all back. I've had a conversation with the franchise in India ... and I won't be playing the full IPL.
"I will come back and play the Test matches against New Zealand next year so IPL is definitely not an elephant in the room any more."
Change of heart
Pietersen added: "I've had a change of heart because I love playing cricket for England, I love being part of a successful England team.
"It would be sad for me to finish with the way things have been running through the media in the last three or four days - it would be sad to end my career like this.
"So sitting down with my family, my advisors, my close friends, we've decided and I've decided it would be a lot better to finish my career on a positive note rather than one that's being developed at the moment."
The South Africa-born batsman expressed his regret for his comments at Headingley and revealed his morale in the dressing room has now improved greatly after a frank and honest chat with an unnamed team-mate.
"There's a press conference I did on Monday night which I didn't handle the right way. I was very emotional. I am who I am in terms of shooting from the hip," he said.
"I do make mistakes. The mood in the dressing room was, I think in the last 24 hours, sorted out.
"I had a really, really, really good long chat to a team-mate of mine yesterday. We went through everything.
"We went through differences, we went through loads of different things and I actually finished that conversation a very happy bloke and someone who can't wait to meet up with the team on Tuesday."
The England and Wales Cricket Board are due to name the squad for the decisive third Test at Lord's on Sunday morning.
England need to win the match to level the series and preserve their position at the top of the International Cricket Council's Test rankings.
Should England pick Kevin Pietersen in all forms of the game?