In 2019 he sent a letter to the Financial Times that accused Greig of being “economic with the actualite” in an interview.
On Mr Dacre’s return, Mr Clarke said: “Nobody has done more to make the Mail titles what they are today than Paul Dacre and I am honoured to be working with him.
“His journalistic courage and judgement are beyond equal and editors and executives the length of Fleet Street can testify personally to how much they owe to his encouragement and counsel.
“DMG Media is extremely lucky to be able to draw on such a legendary talent.”
Mr Dacre was first linked with the £142,500-a-year position overseeing Ofcom last summer and was Boris Johnson’s preferred candidate.
He was viewed as a frontrunner when the Government opted to relaunch the process earlier this year, after the previous selection panel judged him unappointable to the role.
Attempts to install Mr Dacre drew a cross-party backlash, however. Julian Knight, the Conservative culture committee chairman, recently called for ministers to rule out candidates previously deemed unsuitable.
The battle has been waged at a critical time for Ofcom as it prepares to take on responsibility for regulating tech giants, under the Online Harms Bill working its way through Parliament. Mr Dacre has been a longstanding critic of Google and Facebook.
In a letter to The Times, Mr Dacre questioned whether the chief executive of Ofcom, the former senior civil servant Dame Melanie Dawes, was up to the job.
She was appointed after a Downing Street effort to attract private sector candidates for the position was abandoned.
He wrote: “To anyone from the private sector, who, God forbid, has convictions, and is thinking of applying for a public appointment, I say the following:
“The civil service will control (and leak) everything; the process could take a year in which your life will be put on hold; and if you are possessed of an independent mind and are unassociated with the liberal/left, you will have more chance of winning the lottery than getting the job.”
His return comes as Lord Rothermere looks to push through his £850m bid to take the newspaper’s owner DMGT private.
The plans have been cast into doubt, however, after J O Hambro Capital Management – a significant shareholder in the company – joined others in opposing the buyout last week.
