The new chair of Federal Parliament's intelligence committee has reversed his position on whether the Government needs 12 new submarines, and now supports it.

Key points: Andrew Nikolic in 2009 said the Rudd government's figure of 12 submarines was "unscientific"

Andrew Nikolic in 2009 said the Rudd government's figure of 12 submarines was "unscientific" Now says he supports the move

Now says he supports the move Described Mark Dreyfus' "extreme right wing" comments as inappropriate

In 2009 Andrew Nikolic said the figure of 12 submarines was an "unscientific invention" of the Rudd government's 2009 Defence White Paper.

But on Thursday the Coalition confirmed its commitment to 12 subs in its white paper.

Mr Nikolic said he now supported the commitment because it had been properly assessed.

"The way Kevin Rudd went about it was very disaggregated, we might say," he said.

"It's a bit like the back of the envelope calculations for the NBN. The difference here is that we've done an appropriate strategic assessment."

The issue has been a hot political topic in South Australia, with voters wanting 12 submarines to be built to secure jobs.

Mr Nikolic said the Government's commitment was not about winning votes in the state.

The Tasmanian Liberal MP was appointed as the Joint Intelligence Committee's chair yesterday, replacing new Veterans Services Minister Dan Tehan.

Shadow Attorney-General Mark Dreyfus earlier said Mr Nikolic had "extreme" right wing views and his elevation would risk bipartisanship.

Mr Nikolic said it was an inappropriate attack.

"I know it's an election year but I think Mr Dreyfus should know better than to politicise the work of our committee," he said.

"I've been part of a group over the past two years that has produced five bipartisan reports that has improved Government legislation."