"I don't care if I'm starting, or sweeping the floors. You hear me? I want to win," he said.
World Peace and the Knicks came to terms on a two-year deal with the first year guaranteed, a league source told ESPNNewYork.com's Ian Begley. The team did not disclose terms of the deal.
The deal is worth approximately $1.6 million per season with a player option for Year 2, the source said, adding that the Knicks used the remainder of their mini-midlevel exception to sign the former Laker.
According to the amnesty provision of the current collective bargaining agreement, the Lakers will owe World Peace $7.3 million in the coming season.
"Metta is a fierce competitor who brings toughness and championship experience to our roster," Knicks general manager Glen Grunwald said. "We are excited to bring him back to New York and give him a chance to play for the team he grew up rooting for."
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Metta World Peace will work well in rotation with Carmelo Anthony and, as a quotable personality headed back to a town he loves, he'll also clear a few reporters from Anthony's locker, writes Bradford Doolittle. Story
World Peace said that he and Knicks star Carmelo Anthony would be able to "help each other."
"It's not about one person helping one person. It's about us doing it together," he said. "And they have that -- if I'm not mistaken. They have chemistry, and everybody's a teammate."
World Peace had also expressed interest in playing for the Clippers or heading overseas to Shanghai.
"Being in my prime, I think China would have been very inspirational," he said. "But then you get back to that orange and blue and you know that orange and blue blood, you've got to come back home. You've got to come back home."
He referred to the signing on Twitter, poking fun at the division-rival Nets.
Knicks coach Mike Woodson said Sunday that he would welcome the addition of World Peace.
"I know his name has been surfacing out there," Woodson said in Las Vegas, where New York has a summer league team competing. "I can coach any player. I coached guys from 18-, 19-, 20-year-old young men, and built a team in Atlanta, and that's tough for a first-time coach. So I experienced that, and I don't think there's a player I can't coach if he's willing to be coached. ... If anybody comes to this team, they've got to understand it's all about team, man. It's not about individuals here, it's not about me as a coach. It's about the New York franchise trying to win an NBA title. If you understand that, then we've got a chance.
"I like his skill sets a lot. I think a lot of teams have liked his skill sets over the years. He does a little bit of everything."
World Peace said his reasons for joining the team included Woodson, Anthony and Amar'e Stoudemire.
"Melo, Stoudemire, Coach ... that's all it's about right now," he said. "It has nothing to do with New York the city. Only as important as those players I'll be joining."
Information from ESPNNewYork.com contributor Ian Begley, ESPN The Magazine's Chris Broussard and The Associated Press was used in this report.