Barton has fallen foul of the football authorities on occasions

Barton has been involved in several high-profile controversial incidents, but McClaren said the midfielder's reputation was not an issue.

"Joey is a leader with great character. You need forthright people like that, on and off the field," said McClaren.

"He has had his troubles but he has come through them."

McClaren, who saw Barton in action in the Manchester derby at the weekend, added: "He is a player who has matured over the year.

"I tried to buy Joey when I was at Middlesbrough so he is a player who interests me."

England did nothing in that World Cup, so why were they bringing out books? Joey Barton on the rash of post-World Cup books by England players

Barton may have ruffled a few feathers in the England camp with his recent comments about the spate of books which emerged after the World Cup.

Wayne Rooney, Rio Ferdinand, Frank Lampard, Ashley Cole and Steven Gerrard all produced books after the tournament.

"I can't get my head around that," said Barton.

"England did nothing in that World Cup, so why were they bringing out books? If I'm buying a book I'll buy a book about someone who's won something.

"I might be off the mark, but (the England World Cup team) seemed to be a bunch of individuals playing for themselves and not wanting to do the nasty things involved in being a team."

606 DEBATE: Do you share McClaren's enthusuasm for Barton?

England have a friendly against Spain in February before returning to the European Championship qualifying campaign against Israel in March.

And McClaren said that he and his coaching staff had picked out players in the Premiership, including Barton, that they wanted to look at in the England set-up.

"We have a core of about 15 players but we've identified 50 in the Premiership who we're going to concentrate on," he said.

"They will all have an opportunity but, by the end of the season we will bring that down to a more manageable number.

The whole thing is an absolute joke England boss Steve McClaren on rumours that assistant Terry Venables may leave his post

"That will be the squad for the push for qualification to Euro 2008."

Meanwhile, McClaren also moved to dismiss reports that his assistant coach Terry Venables could stand down.

"These stories annoy me and upset me because they are absolute rubbish," he said.

"We speak most days every week. We had the scouts round the other day and we were laughing about it because the whole thing is an absolute joke.

"I don't take on people who are 'yes people' and I don't take on people who are friends.

"I take on people who have the experience and who I believe will help England win.

"The relationship I have with Terry is a relationship we have had from the beginning and one we are developing. Terry is fantastic working with the players and he has fantastic knowledge.