Newcastle will allow Joey Barton to leave on a free transfer following the midfielder's public criticism of the Premier League club.

The infamously combative Barton was runner-up in the vote for Newcastle fans' player of the year award, but publicly criticized the decision to sell key players including captain and leading scorer Kevin Nolan.

Barton repeatedly expressed his dissatisfaction on Twitter and refused to sign a new contract, prompting the club to announce Monday that it was parting with one of the fiercest competitors in the Premier League.

''If I wanted to leave, I'd just come out and say ''I want to leave'' Things need addressing as am not prepared to go through a relegation again,'' he wrote Sunday.

The 28-year-old Barton had said he would make an announcement regarding his future on Twitter, but the club pre-empted his news with a statement on its website.

Barton cost Newcastle 5.8 million pounds (49.4 million) in June 2007 and had one year left on his Newcastle contract.

Since starting at Manchester City, Barton's career has been checkered with disciplinary problems on and off the pitch.