Watford are expected to appoint Rob Edwards as the club's new manager after Forest Green Rovers confirmed his exit.
Roy Hodgson is set to leave the Hornets at the end of the season, having failed to prevent relegation from the Premier League.
Forest Green, who won the League Two title last week, said negotiations between Watford and Edwards took place "behind our backs"."We had no contact from Watford," Forest Green said.
"We thank Rob for all his work at Forest Green Rovers - forgive him the manner of his departure and wish him well."
Speaking to Sky Sports, Forest Green owner Dale Vince said: "Watford advised Rob not to tell us, specifically. That doubles down on the deceit. Deceit is part of a culture that comes from the top."
Edwards, 39, could become Watford's eighth permanent manager since the start of 2018.
He took over at Rovers last summer, having previously coached England's youth teams.
The former Wales international led Forest Green to a first promotion from League Two, having entered the Football League in 2017.
"Rob was a key part of the team that gained promotion to League one this season," Forest Green said. "We're disappointed that our support, loyalty and honesty towards Rob has been repaid in this way."
Edwards has previously managed Wolves on an interim basis and Telford United full-time.
He left Telford to work as a coach in the England Under-20s setup, eventually being named head coach of the country's Under-16s side from 2020 before his move to Forest Green.