Leno to have star-studded farewell

Jay Leno will close out his 22-year run as host of NBC's The Tonight Show with the help of his first ever guest, Billy Crystal.

Jay's final night on the US chat show, on February 6, will feature the When Harry Met Sally star, who was Jay's first guest in May 1992 when he succeeded Johnny Carson. Country superstar Garth Brooks will also appear.

Jimmy Fallon - who is succeeding Jay as host of the show - will also kick off his final week with a guest appearance on February 3. Jimmy is taking over the gig after hosting NBC's Late Night since 2009.

The show host's last week will also include Betty White, Matthew McConaughey, Sandra Bullock, country singer Blake Shelton, musician Lyle Lovett and NBA Hall of Famer Charles Barkley.

Jay briefly left the show in 2009. After a few months hosting his own show, he returned to Tonight in 2010.

Meanwhile, it has been revealed Jimmy will open his run as the host of the show with actor Will Smith and the rock band U2 as guests.

NBC is debuting the Jimmy regime on February 17 at midnight following the Winter Olympics. It will slip into its regular slot following the local news a week later, with Seth Meyers inheriting Late Night.

Jimmy said he had talked to Jay regularly during the transition. One piece of advice that Jimmy has already taken is to increase the length of his monologue.

Although Jimmy is moving Tonight to New York from the West Coast, he said he will take the show on the road - including to Los Angeles for a couple of weeks a year.