Abbott to make call on 'secret' spill

Prime Minister Tony Abbott will make the call on whether the vote on next week's leadership spill motion will be taken in secret, Liberal Party elder Philip Ruddock says.

Tony Abbott is currently battling a move by disgruntled Liberal MPs to oust him and will face a leadership spill motion at a party room meeting next Tuesday.

The unrest in the party comes after disappointing polling and a number of controversial "captain's calls" made by Mr Abbott, including the Australian knighthood awarded to Prince Philip.

Mr Abbott has said he's confident the spill motion will fail and that it will act as an endorsement of his leadership.

Speaking on Saturday, long-time Liberal MP Philip Ruddock said if the spill motion succeeded a secret ballot would follow to determine the leadership.

He said if the spill motion was successful there would definitely be a secret ballot for the leader and deputy leader positions.

But he said it would be up to Mr Abbott to decide whether the spill motion was also decided in secret.

"It's a matter for the leader," Mr Ruddock told the Nine Network.

"The question is whether or not people ought to make it clear what their position is as they ... show their hand in front of everybody else, or whether they do it in a secret ballot."

Mr Ruddock told AAP he had not been advised of any change to the timing of the crucial party meeting, with speculation Mr Abbott may bring it forward to Monday.

At the moment it is set for 9am on Tuesday.