Sir Alex Ferguson has been given a four-match touchline ban and fined £20,000 for his outspoken attack on the fitness of referee Alan Wiley last month.

The Manchester United manager appeared before a four-man panel of the FA’s independent regulatory commission to answer a charge of improper conduct relating to his criticism of Wiley. Ferguson was banned for four games, two of which are suspended until the end of the 2010-11 season, and warned as to his future conduct.

“Each member of the commission recognised Sir Alex Ferguson’s achievements and stature within the game," Peter Griffiths QC, the chairman of the commission, said. "Having said that, it was made clear to Sir Alex that with such stature comes increased responsibilities.

"The commission considered his admitted remarks, in the context in which they were made, were not just improper but were grossly improper and wholly inappropriate. He should never have said what he did say.”

The suspended sanction will be automatically activated should Ferguson be found guilty of a similar charge before the end of the 2010-11 season.

Ferguson was condemned by senior referee officials and threatened with legal action after he claimed that Wiley “just wasn’t fit enough” and “needed a rest” after United’s 2-2 draw against Sunderland at Old Trafford on October 3, even though official ProZone statistics suggested otherwise.

Ferguson said he regretted the personal nature of the attack and made two apologies to Wiley. The Scot has been at war with the refereeing fraternity in recent weeks. As well as his attack on Wiley, he questioned whether Andre Marriner had the experience to referee a Liverpool-United fixture after the match at Anfield almost three weeks ago.

He also tore into Martin Atkinson after United’s 1-0 defeat by Chelsea at Stamford Bridge on Sunday, accusing the referee of being in an “absolutely ridiculous” position when he awarded Carlo Ancelotti’s team a controversial free kick from which they scored the only goal and suggesting that his players were starting to lose faith in referees.