Reports in the English media suggested Australia captain Viduka had been told he was no longer wanted at Middlesbrough, while Nigeria forward Yakubu has been linked with a move back to former club Portsmouth.

Viduka, 30, was one of his country's most impressive performers at the World Cup and several clubs, including Blackburn, are thought to be interested in signing him.

But Southgate is determined to keep both players at the Riverside Stadium and he told the club's website: "The reports about Mark being available are utter rubbish.

"He is a big part of my plans for next season and beyond. I don't need to tell anyone how important he is to our team.

"He is enjoying a well deserved rest now following the World Cup but I look to welcoming him back to training in July."

Yakubu was Middlesbrough's top scorer last season and Southgate will not entertain any offers for the Nigerian international.

He added: "He's 23 and he can only get better. Why would we want to sell him? The great thing with this job is I'm not under pressure to sell anyone."