LeBron James says he could play for another "five to seven years" at a high level despite turning 40 on Monday, but will not choose to do so.

The Los Angeles Lakers star will become the 32nd player to appear in an NBA game in his 40s when he faces former side Cleveland Cavaliers on Tuesday.

He became the youngest player in league history to reach scoring milestones at 1,000 through to 40,000 career points and is playing in his 22nd season, becoming just the second to do so after Hall of Famer Vince Carter.

Already this season, he has broken the NBA all-time appearance record, overtaking Kareem Abdul-Jabbar’s 1,797, and is now on 1,807.

Though James, who helped the United States to another Olympic gold medal in Paris earlier this year, admitted he has thought about retirement more than before, he believes he could go on for even longer.

"I had a decade of the 30s, so to just wake up and just be like, 'Oh, shoot, oh damn, you're 40?'" James said on Monday. "It's kind of laughable, really, to know where I am, to see where I am still playing the game at a high level, still being such a young man but old in the scheme of how many years I got in this profession.

"To be honest, if I really wanted to, I could probably play this game at a high level, probably for about another - it's weird that I might say this - but probably about another five to seven years, if I wanted to. But I'm not going to do that."

James missed the Lakers' last match against the Sacramento Kings through illness but is back with the team ahead of their meeting with his former side.

Despite some Los Angeles struggles – they sit seventh in the Western Conference with an 18-13 record – James has been their star once more, averaging 23.5 points on 49.6% shooting, as well as nine assists and 7.9 rebounds.

However, the four-time NBA champion is not confident of the Lakers' chance of winning the title this season.

"Right now, I think we're a very good team," James said. "I think we have a chance to compete with anybody in the league.

"Are we at a championship level? Can we win a championship right now? No, I don't think so. But that's good because we have so much room for improvement.

"I don't know if that determines if I stick around longer, because it doesn't change my career in any sense or fashion.

"I would love for it to end here. That would be the plan. I came here to play the last stage of my career and to finish it off here. But I'm also not silly ... [not] to know the business of basketball.

"But I think my relationship with this organization speaks for itself. And hopefully, I don't got to go nowhere before my career is over."