Prime Minister David Cameron pulled the plug on cross-party talks on a new system of regulation for the press.
Mr Cameron will now call a vote in the House of Commons on Monday on Conservative proposals for a Royal Charter to underpin the new system.
Both Labour and Liberal Democrats voiced dismay at the break-down of discussions designed to establish cross-party consensus on the sensitive proposals in the Leveson report into phone-hacking.
It is unclear whether Deputy Prime Minister Nick Clegg will tell his MPs to vote with Labour to defeat the Tory proposals.
In a hastily-arranged press conference in 10 Downing Street, Mr Cameron announced that the cross-party talks had “concluded without agreement” after a conference call between himself, Mr Clegg and Labour leader Ed Miliband this morning.
He said that the proposals for an independent body, established by Royal Charter, to oversee the system of press self-regulation would provide “the toughest regulation of the press that this country has ever seen”.
Newspapers would refuse to sign up to a new system which is underpinned by statute, as recommended by Lord Justice Leveson and advocated by Labour, Lib Dems and the Hacked Off campaign group, he warned.
“The route I have set out is the fastest possible way to deliver the strong self-regulation body that Leveson proposed that can put in place million-pound fines, prominent apologises and get justice for victims in this country,” said the Prime Minister.
“The deal is there to be done, it is the fastest way to get proper justice for victims.”