The 28-year-old England striker has missed United's last two games with a groin injury but it was hoped he could return to face Swansea this weekend as the Premier League champions look to end a three-game losing streak in all competitions.

However, Moyes said Rooney had been sent away to sunnier climbs with a fitness coach and his family before a hoped for return at Chelsea on January 19.

"Wayne has been sent away on a sort of hot weather break," said Moyes, who didn't specify where the training would take place.

"His groin has not recovered yet. We have sent the fitness coach with him and he is away with his family.

"I gave him a bit of a break, I always hoped I would be able to do it at some point in the season but his groin is not as good as we hoped at this point.

"Hopefully we can get him fit for Chelsea and we will see how he is. He will do some work with the fitness coach."

"He has an injury, we have to hope he gets better. We have given it a chance to heal but we feel the best thing to do is to let him work in warmer weather and go away with the family and hopefully it will get him better," Moyes added.

The under-pressure manager also said United would be without Robin van Persie, their other star striker, for the Swansea match, with the Dutchman still sidelined by a thigh problem.

Van Persie has not played since suffering the injury when he came on as a substitute in United's 1-0 win over Shakhtar Donetsk on December 10, three days after he made his comeback against Newcastle following groin and toe problems.

The latest injury news adds to Moyes's burden as United head into this weekend's fixtures 11 points behind Premier League leaders Arsenal, with their chances of finishing in the top four and so qualifying for the Champions League also under threat.

Moyes, in his first season as United boss following the retirement of Alex Ferguson, Britain's most successful football manager, tried to keep Saturday's match at Old Trafford in perspective.

"You get three points for winning and don't get more," Moyes said.

"Obviously if you are not winning it can affect confidence and is a big part of football but prior to that we won six games and we were not talking about confidence in the game after that," the Scot added.

"You can lose games in football and we will try to get back to winning ways, try to get back and get those three points.

"I think the performances have been fine. There have been things gone against us, decisions which haven't helped but I think we have played pretty well, need to be more clinical and get into the final third and make things count.

"All the stats are good but only one that matters is goals and we have not scored enough recently."

The former Everton and Preston manager, who endured tough spells in his time at both those clubs, does not believe that this is the most difficult time of his career, despite the enormity of the job on his hands at Old Trafford.

"In management you are going to lose games," Moyes said. "I don't know any manager who hasn't lost games, you have to go through it at some point of your career, I've had it a few times and we are having a difficult time just now.

"I think I have had equally challenging times at other points and they're all the same.

Losing games is difficult. We have had a lot of attention, it was to be expected."