Opposition parties are speaking out against the format being laid out for the long-awaited special debate on Muskrat Falls.

Special debates require consent from all parties before they can proceed.

Earlier this week, Premier Kathy Dunderdale said the debate on Muskrat Falls will mirror the debate on Voisey's Bay 10 years ago, and rejected calls for expert witnesses to be questioned.

But that is not sitting well with the Liberals or the New Democrats.

"If there's no agreement between the three parties, and Kathy Dunderdale is saying, here's how we're doing it, Eddie Joyce will vote against it," said Liberal MHA Eddie Joyce.

"You have my word that, if she's trying to push this Voisey's Bay format, Eddie Joyce will stand and say, 'I will not accept it,'" he said, adding that the two projects can't be compared since Voisey's Bay involved private money.

The NDP said the government must show some flexibility with the debate over Muskrat Falls.

"If you're as confident about that as you are, sit down and have an agreement, a tripartite agreement amongst the three parties, as to what's the appropriate format for this debate," said New Democrat MHA Dale Kirby.