And the Manchester United boss, who has long been renowned as the master of football brinkmanship, has denied using psychological warfare in a bid to scupper Arsenal's title challenge.

'Discipline is an important element' - Martin O'Neill speaks to Radio 5 Live

He said the comments, which appeared in a Sunday newspaper, had been made in a private context and he had never intended for them to be reach the public arena.

Ferguson said: "Arsene Wenger has a right to be annoyed over this matter. I have already dropped him a note explaining the situation and I offered him the apology he deserved.

"It is not my policy to criticise other teams and the way they play. The last thing we want is to have big clubs like ours in this sort of confrontation.

"People go on about it all being psychological warfare, but that is far from the truth on this occasion," he said.

'I was stitched up'

The Scot has developed a reputation for using psychological tactics against his closest rivals - most spectacularly when Newcastle manager Kevin Keegan was provoked into an emotional outburst live on TV during his side's capitulation in the 1995-96 title race.

Wenger: 'We have a good image'

But this time Ferguson denied accusations of underhand dealings.

"I was stitched up and I feel I have been betrayed. The conversation was off the record," he told The Sun.

Before Ferguson's apology, Wenger shrugged off Ferguson's claim that the Double winners' success was derived from their "belligerence".

"It doesn't bother me at all," he said. "It's just, I think, a clumsy statement to make.

"We don't need to start fights to win matches. I think what he said was wrong.

"It's disappointing to hear another manager talk like that. I personally think we have to keep a good image of our game and that starts by respecting every other team.

"You don't win championships or win cups by just fighting. It is wrong to say things like that.

"If you look at the Fair Play table we have got 37 yellow cards and Manchester United have got 38. Many other teams have got more."

Another leading Premiership manager, Martin O'Neill of Leicester, believes good discipline can be key to a team's success.