The Prime Minister’s Department has been accused of neglected its Indigenous affairs duties.

The department faced over 50 questions when it a Senate committee hearing late last year, which it pledged to respond to at a later date.

Three months later, the agency appears to have left many answered.

“I think the delay by the Government in not answering these questions is really about hiding the truth behind what they're doing,” NT Labor Senator Malarndirri McCarthy told reporters this week.

“This is an arrogant Government that does not want to share, or care, about its process in Indigenous affairs.

“It just shows that they're not serious in relation to Indigenous issues in this country.”

The questions related to the troubled Indigenous work-for-the-dole scheme, Constitutional change, and the rejected Uluru Statement.

“For such a well-resourced department, it is concerning that the Department of the Prime Minister and Cabinet has not answered a single question asked in October last year,” said Greens Senator Rachel Siewert.

“The questions asked are important and should be answered, particularly on Aboriginal issues where there are many pertinent issues that need addressing.”

The department is responsible for most Aboriginal and Torres Strait Islander programs, but managed to answer about three quarters of the 100 questions it was asked about non-Indigenous issues.