The Sinn Fein chair of the assembly's finance committee has accused Sammy Wilson of making unhelpful comments over the budget.
Jennifer McCann said that ministers should "not be going on solo runs" after the finance minister warned time was running out on an agreement.
Mr Wilson said he was frustrated over the Executive's failure to deliver a draft budget.
He had warned that an emergency budget might have to be brought in.
In a letter to the finance committee, he asked members to acknowledge the urgent need to agree a draft budget.
The finance committee chair Jennifer McCann said it was important that the Executive gets the right budget, insisting more information is needed from the Treasury.
"All the Executive needs to sit down together and plot a way forward and plot a draft budget," Ms McCann said.
"I don't think it's helpful when certain ministers go public or go on a solo run if you like, we need to send out a united voice."
Ulster Unionist MLA David McNarry, who sits on the finance committee, said he was sympathetic to the minister's position on the damage and instability created by further delay.