Sources close to McDermott are denying allegations from Cellino that the 53-year-old had taken a holiday and was uncontactable at a time when United’s president is implementing widespread cuts and changes at Elland Road.
An angry Cellino vented frustration at McDermott in a television interview on Wednesday, saying the club was “not managed by anybody” and claiming to be unaware of McDermott’s whereabouts.
Cellino said: “I think at this moment the club is not managed by anybody. Who’s managing this club? Brian. Where’s Brian?
“I sent a letter to Brian – help us. He’s on holiday to get some rest. He was tired, I can understand. But why this kind of reaction?”
McDermott is understood to have left his home in Harrogate last week, travelling to visit his ill mother. He was present at the League Managers’ Association’s awards ceremony in London on Monday night and has remained down south since then.
Friends of McDermott’s say he has been available to a speak to Cellino throughout the past week but has not been contacted by the Italian, other than through written communication.
The former Reading boss, whose strained relationship with Cellino is threatening to end his 13-month tenure at Leeds, has had no verbal contact with his owner since the end of the season but received a letter from Cellino last Thursday, asking him to explain the absence of players and staff from Thorp Arch and outline his plans for the squad and pre-season.
McDermott has replied in writing, providing details of the fitness programmes given to United’s senior professionals and setting out a proposed pre-season schedule. The club are yet to finalise any friendlies or a summer tour.
But his position as manager is more fragile than ever after a week of major developments at Elland Road. Cellino launched a formal redundancy process on Wednesday and has drawn up a retained list with the help of Benito Carbone, the ex-Bradford City striker who began working for Leeds towards the end of last month.
The retained list, which should be announced today and reveal which of United’s out-of-contract players are to be offered new deals, was compiled without any input from McDermott.
First-team and development-squad coach Neil Redfearn was asked by Cellino to offer advice on United’s young professionals, and youngsters Nathan and Lewis Turner - twins who came through the academy at Thorp Arch - confirmed on Twitter yesterday that they are to leave the club this summer.
McDermott also appears to be heading for a parting of way with Leeds, though Cellino is known to be reluctant to foot a £1.5m bill by severing a contract which ties McDermott to United until 2016.
The LMA has been assisting McDermott since Cellino’s failed attempt to sack him in January but the organisation did not respond to a request for comment last night.
Carbone, meanwhile, is becoming increasingly prominent at Elland Road, and Leeds have officially confirmed his appointment to their staff, describing him as a “consultant” who will “deal with technical and football operations.”
The former Sheffield Wednesday player linked up with Leeds in the final week of April, with Cellino saying initially that he would “help me rebuild the academy.”
But a statement published by the club yesterday said Carbone, 42, would be “involved with all football matters, including both the first team and the academy.”
In a separate development, it emerged that secretary Alison Royston has been suspended by the club. Neither Leeds nor Royston have commented on the reason for her suspension.