Sven-Goran Eriksson's growing distrust of Alex Ferguson is threatening a total breakdown in their working relationship after the Manchester United manager's allegation that the England coach had "shaken hands" on a deal to break his contract with the English Football Association to take over at Old Trafford.

Eriksson is incensed by what he perceives as a calculated attempt to undermine him when, perhaps for the first time, serious questions are being asked about his ability to lead the national team.

He has also been angered by Ferguson's withering portrayal of him as a yes-man who follows the whims of the media, such as appointing David Beckham captain.

Relations between the two managers have become increasingly strained over the past few months and there is a deep suspicion in the Eriksson camp that Ferguson, a notorious stirrer, is actively seeking to destabilise him.

Having repeatedly denied the link with Old Trafford ever since it was reported early last year, the Swede is acutely aware he now faces an allegation of duplicity. If Ferguson's claim is correct it could also be perceived that he had been disloyal to the FA, which was not privy to negotiations about the Swede succeeding Ferguson after his planned retirement last season.

"Sven's more than a little embarrassed. Quite frankly he's pissed off," said a source close to the England coach. "You shake hands only when a deal is done. And no deal was done here. That's a fact. Sven wants to know why he (Ferguson) has said this. And why he has chosen now, of all times."

Ferguson's mischief-making has also provoked the ire of United's board and yesterday's attempts to backtrack will do little to appease the chief executive Peter Kenyon.

Kenyon privately conceded that he had "sounded out" Eriksson, an admission that is sure to irritate the FA, particularly given its attitude towards clubs making approaches to managers under contract elsewhere.

Eriksson was so enamoured by the prospect that he spoke to Ferguson's former assistant Steve McClaren about leaving Middlesbrough to go back to Old Trafford as his right-hand man, an invitation that went down well. Eriksson was pondering what to do, knowing how unpopular a decision it would be to resign, when Ferguson reversed his decision to retire.

However, the negotiations never reached the stage where Athole Still, Eriksson's agent, became involved.

"There must have been hundreds of occasions when Kenyon sat next to Eriksson at a game or an official function and could have had a quiet chat with him," said the source. "But proactively, zero happened."

That differs from Ferguson's account of things.

"I think they'd done the deal all right," he says in a magazine interview. "I don't know for certain but I think it was Eriksson. I think they'd shaken hands. They couldn't put anything on paper because he was still England manager."

The damage done, Ferguson sought to "clarify this thing with Eriksson" yesterday, saying it was just informed guesswork.

"I was just offering my personal opinion. It was only what I had heard (unofficially). I've no idea, to be truthful, who they approached. Nobody here has ever told me officially and I swear that on my life and my kids' lives. If I had been involved (in the selection process) I can understand people would take it as fact that Manchester United approached the manager of England. But there's no way I knew it for sure.

"When I spoke to Peter Kenyon and Sir Roland Smith (the plc's now retired chairman) at the start of last season, I told them it would be unfair to involve me because I could want someone who was a friend of mine and they had to be more objective. And I think they did that. But, again, I swear on my kids' lives, I didn't know for sure."

That begs the question as to why, if he were not certain of the facts, Ferguson chose to divulge his second-hand information to a magazine, something that was hardly addressed with his observation that "I didn't think they were going to use it".

He was equally unsatisfactory in explaining his perceived criticisms of Eriksson. A man of his experience will have recognised the potential for headlines in his unflattering appraisal of the Swede.

"I think he would have been a nice choice in terms of nothing really happens, does it?" he told the magazine. "He doesn't change anything. He sails along, nobody falls out with him. He comes out and says 'the first half we were good, the second half we were not so good. I'm pleased with the result.' The press make a suggestion, he seems to follow. Making Beckham captain, for instance. I think he'd have been all right for United, you know what I mean? The acceptable face."

Yesterday Ferguson said his comments should not be taken as a slight on the England coach.

"I was talking about the differences between our styles: Sven's laid-back style and the aggressive way I manage. After 15 years of me I think Manchester United definitely needed someone with a different approach. In my opinion Sven was the best man for the job. I know it looks bad but I don't think it was a criticism."

It was odd how relaxed Ferguson seemed, unusually convivial with the press and making light of last week's contretemps with Beckham, joking he would line up eight football boots and kick them at anyone who asked a bad question. "Eight yards it was (to Beckham) - a magnificent hit."

Eriksson's mood will have been significantly less jovial. He and Ferguson have never been close but it is clear the damage to their relationship caused by the United manager picking Paul Scholes for a match in September, two days after telling the England coach the midfielder was not fit for international duty, has now developed into a serious rift, one that might be irreparable.