AAP

Treasurer Wayne Swan has accused Opposition Leader Tony Abbott of letting maverick Nationals Senate leader Barnaby Joyce write the coalition's foreign investment policy.

Mr Swan made the comments after Mr Abbott hinted at tighter restrictions on Chinese state-owned firms investing in Australia during a speech in Beijing.

On Tuesday, Mr Abbott said that while he welcomed Chinese investment, it was complicated by the dominance of state-owned firms.

Mr Swan said current existing Foreign Investment Review Board guidelines on sovereign company investments were working well.

"I actually think that it's very damaging for Australia that foreign investment policy in the Liberal-National Party has now been taken over by Barnaby Joyce," Mr Swan told reporters in Sydney.

"There's a pipeline of investment that is coming our way ... creating jobs and wealth in Australia.

"Now Mr Abbott wanders off overseas and puts a very big question mark over all of that because he wants to play politics while he's wandering around the world."

Earlier, Climate Change Minister Greg Combet said Mr Abbott had shown he knew less about market economics than China's communist party.

Mr Abbott had shown complete ignorance about the steps China was taking to price carbon during his trip to Beijing, Mr Combet said on Wednesday.

"Even the Chinese communist party (has) a better grasp of market economics than the leader of the Liberal Party does," he said.

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