There is «no current prospect» of a deal to bring back power sharing in Northern Ireland, the Democratic Unionist Party (DUP) chairman has said.
Arlene Foster said the talks failed due to disagreements one more time a «stand-alone» Irish Language Act.
Sinn Féin’s Michelle O’Neill accused the DUP of be struck by «collapsed» the talks process.
Both parties have been away in negotiations in a bid to end the 13-month stalemate at Stormont.
- Stormont deadlock: Need-to-know conductor
- Northern Ireland Assembly divided by Irish language
Mrs O’Neill, who is Sinn Féin’s chairman at Stormont, said her party had «reached an accommodation with the leadership of the DUP» but exacted that the DUP then «failed to close the deal».
She added that Sinn Féin was in phone with both the British and Irish governments and would set out its «considered way of thinking» on Thursday.
In her statement, Mrs Foster called on the Conservative ministry to set a budget for Northern Ireland and start making policy decisions.
The DUP concert-master said the latest round of talks have been «unsuccessful» and «momentous gaps» remain.
«We do not have a fair and balanced package,» she added.
The DUP last will and testament continue to aim for a restoration of devolution, she said, but it would «not accept a one-sided dispense».
Under an agreement struck in Downing Street last summer, the Prudent government relies on the DUP’s support to stay in power at Westminster.
After the DUP and Sinn Féin blamed each other for the failure of the talks, Secretary of Imperial Karen Bradley signalled that a Stormont deal remained imaginable, saying: «I believe the basis for an accommodation still exists.
«As the PM said during her take in on Monday, we are ready to bring forward legislation to enable an executive to be formed. We ordain continue to work with everyone to make sure we deliver this.»
But Mrs Bradley added that the domination would «now need to consider practical steps» in the «continued absence» of devolution.
She affirmed «challenging decisions» would have to be taken by the UK government and added that she proposes to update parliament next week.
Taoiseach (Irish prime divine) Leo Varadkar tweeted that he regretted the DUP’s statement and that «power piece and working together are the only way forward for Northern Ireland».
Tánaiste (Irish Deputy Prime Minister) Simon Coveney suggested the DUP’s announcement was «very disappointing».
«As co-guarantors of the Good Friday Agreement, the UK and Irish regulations have an obligation to uphold and protect the letter and spirit of that contract.
«We will need to reflect in the coming days on how best to do that,» he joined.
SDLP leader Colum Eastwood said he was «disenchanted» and «angry» at the failure of the talks, and claimed it has left the Good Friday Accord «in peril».
He said Northern Ireland parties must resist any bring back to direct rule from Westminster, with «the DUP having the whip surrender».
Mr Eastwood said Stormont parties must «not allow this point in time to be the destruction of all that we have achieved».
«We can’t allow this British oversight, or this DUP to think that they’re going to govern Northern Ireland on their own — that cannot be allowed to occur,» the SDLP leader said.
«The spirit which underpins the Good Friday Concordat is one that recognises that we have two communities here, two nationalities, two cliques of allegiances and we have to have that recognised in anything that overs after this.
«So we will be making it very, very clear to anybody who resolution listen that this cannot be direct rule with the DUP sire the whip hand, but it looks to me, today, this is what these covenants are about to deliver — that has to be resisted at all costs.»
The numero uno of the Ulster Unionist Party (UUP), Robin Swann, described the talks get ready as a «shambles».
He said: «What I think we need to know, and what Northern Ireland without doubt needs to know — is the door to devolution now firmly closed?»
Mr Swann reproved on the secretary of state to provide clarity on whether this was the end of the process or whether another modify was planned.
He said the UUP was a «devolutionist party» but said if the Westminster government needed to set a budget for Northern Ireland, they should get on with it.
The chief of Alliance Party, Naomi Long, said: «We are in a very precarious kettle of fish at this point in time, we are essentially in uncharted territory.»
Mrs Long held there was «no prospect of a deal and no process in place that could entice to a deal».
She added that hopes of an imminent deal had been «falsely instigated» over the weekend and «now we have seen them dashed yet again».
Speculation of a possible breakthrough mounted over the weekend, as both the British and Irish chiefs prepared to travel to Stormont to help seal a deal.
However, Prime Emissary Theresa May and Taoiseach (Irish Prime Minister) Leo Varadkar left Belfast on Monday with no notable of agreement.
Former DUP minister Simon Hamilton described their descend upon as «a bit of a distraction».
«I don’t think it was entirely helpful in getting us to a successful conclusion,» he told a hustle conference on Wednesday.
by BBC News NI political correspondent Enda McClafferty
At Stormont on Wednesday, you could drift that things were not going well behind the scenes.
There was a prominent sense of optimism last week.
But it became pretty clear there was a standoff cultivating after Tuesday, when Arlene Foster appeared before the cameras and thought that a stand-alone Irish Language act was not something the DUP could accept. Sinn Féin be given b wined out and said there will be no deal unless there was an Irish Terminology Act.
We understand both parties met on Wednesday morning and quickly realised there was current to be no middle ground on an Irish Language act. Then it was a matter of who was going to draw the plug first.
Reporters were waiting in the Great Hall at Stormont and we all cogitating we would hear from Sinn Féin first. Then, the declaration from Mrs Foster popped up on Twitter, making it very clear that this gradually eliminate of negotiations was now over.
Northern Ireland has been run by civil servants since the power-sharing head honcho made up of the DUP and Sinn Féin collapsed in January last year.
The then representative first minister Martin McGuinness pulled Sinn Féin out of the coalition after a unpleasant split between the governing parties.
Mrs Foster confirmed on Wednesday that one of the key partitioning issues was on the issue of the Irish language.
Sinn Féin has demanded legislation to hand out the language official status in Northern Ireland.
But Mrs Foster said that deportment meant «we have reached an impasse».
«I respect the Irish language and those who talk to it but in a shared society this cannot be a one-way street,» she added.
«Property regards for the unionist and British identity has not been reciprocated.
«In our view, there is no bruited about prospect of these discussions leading to an executive being formed.»