Culture secretary Nadine Dorries became embroiled in a row with TV presenter Kirstie Allsopp over the privatisation of Channel 4, after saying the broadcaster’s “salad days are in the past”.

The pair exchanged messages on Twitter after an opinion piece by Dorries was published in the Mail on Sunday, addressing the government’s decision to push ahead with its plans to sell off the channel.

Dorries wrote that former Conservative prime minister Margaret Thatcher, who set up Channel 4 in 1982, had ultimately wanted it to be “free from the constraints of the state” and described any opposition to the move as “lazy, overwrought and ill-informed rhetoric from the Leftie luvvie lynch mob”.

Allsopp, who presents property show Location, Location, Location on Channel 4, responded on Twitter, questioning whether it was “really ministerial” to describe those contesting privatisation as a “lynch mob” while “at the same time complaining about having been accused of fascism”.

Sharing an article about the US Senate passing an anti-lynching bill, she added: “This piece might make you think twice about using the term.”

The government confirmed last week that it will proceed with plans to privatise Channel 4, which has been publicly owned since it was founded in 1982 and is funded by advertising.

Allsopp responded to the announcement by tweeting that “no true Conservative would sell Channel 4” and that “Lady T will be spinning in her grave”.

Replying to her posts in the evening of Sunday 10 April, Dorries suggested that Margaret Thatcher’s memoirs, The Downing Street Years, proved she intended Channel 4 to be sold.

She also said Channel 4 could not be preserved in its current state because of “decreasing advertising revenue and decreasing investment in new content”.

“There is of course the bonus a sale will bring to the entire sector which is that the proceeds of sale will be invested back into people from all backgrounds, especially those from left-behind communities because talent is everywhere, not just in the SE,” she said.

“We will invest in skills in order to benefit from incoming demand due to our booming film and TV sector due to the favourable tax benefit/relief and funding this gov has put in place to encourage film industry to regard Britain as its home.

“I also love C4, especially Location Location [Location], but as I say in my article, it’s time to look to the future. The channel’s salad days are in the past. Being owned by the gov is restrictive. Time for C4 to fly the nest towards a very exciting future.”

Plans for the sale will reportedly be set out in a White Paper later this month and will be included in a new media bill for next spring.

A string of Tory MPs and peers, including Sir Peter Bottomley, former Scottish Conservative leader Ruth Davidson, chairman of the Digital, Culture, Media and Sport (DCMS) committee Julian Knight, and former cabinet ministers Damian Green and Jeremy Hunt have publicly questioned the plans.

Sir Peter, who represents Worthing West, said he opposes the sale “because I am a Conservative”.

On Monday 11 April, Lucy Powell, Labour’s shadow culture secretary, dismissed the suggestion the sale of Channel 4 would help the regions.

She tweeted: “Selling off C4 to a foreign media giant is the opposite of levelling up. It will cost jobs in Yorkshire and across the North where C4 has been investing for years.

“Apprenticeships, HQ and support for independent productions companies are all at risk.”