Arsenal full-back Gael Clichy has signed a four-year deal with Premier League rivals Manchester City.
The 25-year-old moves to Eastlands for a reported fee of £7m.
The defender, who joined the Gunners from French club Cannes in 2003, is City boss Roberto Mancini's first signing of the summer.
"I'm really happy to be joining such a great club. I hope I can add to the quality we already have here because we have a fantastic squad," he said.
"I can't wait to get started and I think anything is possible with this team."
The defender, who joined the Gunners from French club Cannes in 2003 and has 10 France caps, will contest the City left-back position with Aleksandar Kolarov.
Gael Clichy in focus
- Made his Arsenal debut on the same night as Cesc Fabregas - in a League Cup win over Rotherham in October 2003
- At 18 years and 10 months, Clichy became the youngest player to win a Premier League medal in 2004
- Made 266 appearances for Arsenal, scoring two goals
- Has won 10 caps for France, and featured in their squad for the 2010 World Cup
And the Frenchman immediately directed a jibe at his new side's closest rivals, Manchester United.
"I understand that the people who live in Manchester are the true fans - they are from City," he told the club's official website. "That is a good point. I won't be bothered by United fans."
Clichy reportedly told Arsenal he wanted to leave last month and had also been linked with Liverpool and Roma.
The Frenchman spent the first half of his career with Arsenal as cover for Ashley Cole but became a regular in Arsene Wenger's side over the past five seasons following Cole's move to Chelsea.
Former Arsenal defender Martin Keown believes that selling Clichy represent a "good bit of business" for Arsenal.
"He was making mistakes at key moments and he wouldn't have been especially pleased with what he achieved at the club," said Keown.
"Whether or not Kieran Gibbs is going to be the replacement or not, I still feel that Wenger should buy another left back."
Clichy will be officially unveiled during City's forthcoming tour of the United States and Canada.
His move comes at a tricky time for Arsenal boss Arsene Wenger, with playmaker Cesc Fabregas again being linked with Barcelona.
Midfielder Sami Nasri has also been tipped to leave the club and is thought to be a target for both Manchester City and Manchester United.