Sinn Fein's John O'Dowd has repeated his party's assertion they will not go into government if Arlene Foster's is put forward as First Minister.
It comes as DUP MP Gavin Robinson raised the possibility that she might step aside as the party’s First Minister designate until the RHI inquiry has concluded.
He stressed it would be for Arlene Foster alone to decide but said his party was keen to make devolved government work.
“As a party that wants to see devolved government in Northern Ireland succeed we are not going to present impediments to progress,” the East Belfast MP told Stephen Nolan on Radio 5 Live. “But we are not going to have another party determine who is going to lead our party.”
Mr O'Dowd, who was returned as an MLA for Upper Bann, said his party, as they said during the election campaign, could not support a nomination for Arlene Foster as First Minister and they would not return to government.
Responding, the DUP's Simon Hamilton said he would like to see Arlene Foster lead the party into the negotiations.
Asked if she should step aside, he said: "No she shouldn't. It is not for Sinn Fein to dictate our nominee."
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