A senior Democratic Unionist negotiator has accused Sinn Féin of peddling "doom and gloom" misinformation about the state of talks to restore powersharing in the North.
Jeffrey Donaldson claimed the republican party was misleading the public after its Stormont leader Michelle O'Neill delivered a bleak assessment of the ongoing negotiations.
On day three of the two-week process, Ms O'Neill claimed a deal to rescue the crisis-hit devolved institutions could only be achieved with a "step change" in approach from the DUP and the UK government.
Mr Donaldson responded in robust terms, questioning whether Sinn Féin actually wanted to reach agreement.
"I very much regret that Sinn Féin seem to be the doom and gloom merchants who are falsely accusing other parties of not engaging," he said.
The Lagan Valley MP added: "DUP and the government and the other parties have attended every meeting, have been actively engaging and we believe all of the parties are actively engaged. In fact the only party who we believe has been holding back in these discussions is Sinn Féin.
"Having listened to Michelle O'Neill's comments today it raises a serious question in our mind as to the level of commitment that Sinn Féin are giving to this process.
"Instead of being doom and gloom merchants they should be at the table being more constructive about trying to find solutions."
Ms O'Neill said while there had been numerous meetings involving the UK and Irish governments and Stormont's five main parties, the discussions were not producing results.
"We have seen no progress to date - nothing that we could report that's anything significant," she said.
Northern Ireland Secretary of State James Brokenshire instigated the 10-day talks initiative after last month's negotiations to form a new powersharing administration ended in failure.
Parties missed a deadline to get a government up and running within three weeks of March's snap Assembly election.
Devolution crashed in January over a row about a botched green energy scheme.
The subsequent election campaign laid bare a series of other vexed disputes dividing the two main parties - the DUP and Sinn Féin.
Two of the main stumbling blocks in the way of a successful outcome are the contentious issues of Irish language protections and how to deal with the toxic legacy of the Troubles.
"So far we have had a lot of meetings, a lot of engagement but not a lot of progress," said Ms O'Neill.
"It is very clear to us that the DUP and British government have failed to focus on the key issues of the recent election. Our position is very clear - we will not return to the status quo."
Ms O'Neill said the UK government was standing in the way of progress on legacy issues.
She said movement was also needed on equality issues.
"We want these institutions to work, we want them to deliver for all citizens, but that's the very point - they have to deliver for all citizens on the basis of equality, respect and integrity."
The Mid-Ulster Assembly member said her party would remain engaged in the process throughout.