NEW YORK — NBC on Wednesday announced its long-rumored switch in late night, replacing Jay Leno at the “Tonight” show with Jimmy Fallon and moving the iconic franchise back to New York.

Fallon will take over in about a year, the switch coinciding with NBC’s Winter Olympics coverage next year. Veteran “Saturday Night Live” producer Lorne Michaels also will take over as executive producer of “Tonight.”

NBC made no announcement on who would replace Fallon at the 12:35 a.m. “Late Night” slot, although Seth Meyers of “Saturday Night Live” is considered a strong candidate.

The change at “Tonight,” the longest-running and most popular late-night talk show, had been widely reported but not confirmed by the network until Wednesday. NBC reportedly just wrapped up negotiations with Fallon on a contract extension.

Steve Burke, chief executive officer of NBC Universal, said the network is purposefully making the move when Leno is still at the top of the ratings, just as when Leno replaced Johnny Carson at “Tonight” in 1992.

“Jimmy Fallon is a unique talent, and this is his time,” Burke said.

Leno, in a statement, offered his congratulations to Fallon.

“I hope you’re as lucky as me and hold on to the job until you’re the old guy,” he said. “If you need me, I’ll be at the garage.”

Fallon said: “I’m really excited to host a show that starts today instead of tomorrow.”

The Leno-Fallon changeover didn’t begin smoothly. Leno had been cracking jokes about NBC’s prime-time futility, angering NBC entertainment chief Robert Greenblatt, who sent a note to Leno telling him to cool it. That only made Leno go after NBC management much harder.

The first public effort toward making the transition smooth came Monday night, when Leno and Fallon appeared in a comic video making fun of the late-night rumors. It aired in between each man’s show.