Australian Greens leader Christine Milne has spoken with Treasurer Joe Hockey about a proposal to scrap the national debt ceiling.

The government’s original plan to lift the ceiling by $200 billion to $500 billion has been opposed by Labor and the Greens which want it limited to $400 billion.

However, the Greens are prepared to let the government scrap the ceiling in exchange for greater transparency in what debt is actually being raised for.

Senator Milne confirmed on Tuesday talks with the government on this option are continuing.

“It is mainly at the officer level but I had a conversation with the treasurer last night and we will be having ongoing conversations,” she told Sky News.

The current $300 billion limit will be hit on December 12.

Senator Milne rejected government claims there could be a looming crisis, saying the coalition could accept the Greens’ offer to raise the ceiling to $400 billion.

“They’re the ones who have created this whole silly theatre on debt,” she said.

The government’s legislation remains in the Senate awaiting further debate.