By James McCann

Manchester City manager Roberto Mancini has claimed that the standard of refereeing in English football is slipping, pointing to a number of high-profile mistakes in recent weeks to illustrate his point.

Only last weekend, Martin Atkinson awarded Chelsea a goal in their FA Cup semi-final against Tottenham despite the ball clearly not crossing the line - a decision that had a significant impact on the remainder of the match as Spurs were forced to chase the game.

The week before, Chelsea were again fortunate to be awarded both of their goals in a 2-1 win against Wigan, despite valid claims that each goal was offside, and Mancini said standards need to be tightened with so much on the line.

"When I was in Italy I always thought [in the UK] there were the best referees. My idea has changed. In Italy we say every place is the same. The rules are not the same for everyone," he added.

The Man City boss refused to comment on whether he was referring to two decisions recently awarded in favour Manchester United, but said there appears to be a lack of consistency across different games and referees.

In United's 4-0 home win against Aston Villa last Sunday, Ashley Young won a controversial penalty after going to the ground very easily in the Villa area - a tumble that even Sir Alex Ferguson conceded was exaggerated.

The week before, Young was again in the spotlight when he was the recipient of a challenge by QPR's Shaun Derry that was deemed red card-worthy by referee Lee Mason, despite minimal contact being made – something which invoked the ire of Rangers boss Mark Hughes.

With City sitting five points behind United in the Premier League table and the teams set to collide once more before the end of the season, Mancini said it is important that no more mistakes are made, as one error could decide the outcome of the title race.