Labor demand PM reveal Heydon pay

Labor has demanded Prime Minister Tony Abbott reveal how much unions royal commissioner Dyson Heydon is paid.

In a letter to Mr Abbott on Sunday, opposition employment spokesman Brendan O'Connor said the public had a right to know the taxpayer-funded salary of Mr Heydon.

He said the opposition had "serious concerns" about the government's failure to publicly account for Mr Heydon's salary, accusing the government of frustrating public scrutiny by claiming the matter was "commercial in confidence".