NEW YORK (TheStreet) -- Australian mining stocks gained in Australia but were mixed in London Thursday after Julia Gillard, who ousted Kevin Rudd as Australia's prime minister, said she is open to negotiations over the proposed resources tax.

"I have said to the mining companies of this nation publicly that the government is opening its door, and we are asking them to open their minds," Gillard told Australia's parliament.

BHP Billiton ( BHP), the world's largest mining company, gained 1.3% in Australia to A$39.65, while Rio Tinto ( RTP), the world's third-biggest mining company, rose 1.7%. Macarthur Coal, the world's biggest exporter of pulverized coal, jumped 6.4% to A$12.34. Yanzhou Coal Mining ( YZC), which acquired Felix Resources, an Australian coal explorer last year, increased 1.9% in Hong Kong.

However, BHP and Rio fell 1.3% and 2.4%, respectively, in London on weakened commodity prices and on speculation that the new prime minister will stick to the tax.

Cautiously encouraged by the government's move and as a sign of good faith, both BHP Billiton and Rio Tinto have suspended their anti-resources super profits tax. Rio Tinto said, "This commitment is, of course, dependent on the government's willingness to properly engage on the threshold issues."

"It's a very dramatic development," Stephen Halmarick, Sydney-based head of investment-markets research at Colonial First State Global Asset Management, which manages about $135 billion, told Bloomberg. "The markets will be looking to her to move quite quickly to stabilize the debate and come to a resolution."

Disagreements between the industry and the Australian government in recent weeks contributed to the ouster of Prime Minister Kevin Rudd.