Rupert Murdoch was urged to bow to the will of Parliament today after it emerged that all three main parties are set to back a call for him to abandon his takeover bid for BSkyB.
The Tories and the Liberal Democrats said they would be supporting a motion tabled by Labour leader Ed Miliband when it comes before MPs tomorrow.
The text insists it is "in the public interest for Rupert Murdoch and News Corporation to withdraw their bid for BSkyB".
Mr Miliband said: "I welcome news that the Government says it will support our motion.
"It is now for Rupert Murdoch to recognise the strength of public feeling and the will of all the major parties."
The development comes as the Prime Minister, his Liberal Democrat deputy Nick Clegg and Mr Miliband prepare to hold talks this evening on the phone-hacking scandal.
Labour has called a debate on the row on one of the regular Opposition Days, when it has the opportunity to determine the subject for discussion on the floor of the House of Commons.
News Corp's bid to buy the 61% of shares in the satellite broadcaster which it does not already own was referred to the Competition Commission by Culture Secretary Jeremy Hunt yesterday.
Support for the motion will give Mr Hunt more strength in sticking up for public opposition to the takeover, Mr Miliband said.
He said: "Jeremy Hunt will get a chance to make a decision about the public interest at the end of this process, once it comes back from the Competition Commission.
"We think that if the House of Commons expresses a clear view about what is in the public interest - for the bid to be withdrawn - then that will help him in making the right call."
Mr Hunt is not expected to take part in the vote tomorrow.
David Cameron's spokesman said the Government was "intending to support" the call tomorrow.
Asked whether the Government believed that News Corp should heed the will of Parliament, the spokesman replied: "Ultimately, that is a decision for News Corp but we would always expect people to take seriously what Parliament has said."
Sources close to Mr Clegg confirmed that his Liberal Democrats would also be voting in favour.
The vote will follow the Opposition Day debate tabled by Labour.
In a scathing letter to Mr Murdoch this evening, three senior Lib Dems demanded that he give up efforts to gain full control of BSkyB.
Deputy leader Simon Hughes, party president Tim Farron and culture spokesman Don Foster wrote that recent revelations had "shocked and sickened the British public, and rightfully so".
"News International is simply no longer respected in this country," they wrote. "Given the history of the last six or more years, it should be of little surprise to you that many people in this country have no desire to have any more of our media fall into your hands, tainted as News International is by a history of completely unacceptable journalistic practices.
"News Corporation, as the owner of News International, must take some responsibility for this.
"Two days ago the Deputy Prime Minister Nick Clegg said you should do the decent thing and withdraw your bid to take full control of BSkyB. Many others have said similar things.
"We hope you will respect the widespread expressions of public opinion and change News Corporation's commercial strategy in this country."
"We therefore ask, both on behalf of our party but also on behalf of a very large number of people in this country, that you now withdraw your News Corp bid for BSkyB and concentrate all of your efforts on cleaning up News International."