HONG KONG ? Asian markets were mostly up Thursday as news that Australia's prime minister had resigned lifted hopes that a planned controversial resource tax may be softened.

However, gains were muted by a US Federal Reserve statement that suggested the European debt crisis was taking a toll on recovery in the world's biggest economy while fresh data showed new home sales had hit a record low.

Sydney rose 0.62 on opening after Prime Minister Kevin Rudd stood aside from a party ballot that looked set to oust him following a surprise party coup.

He has been succeeded by Julia Gillard, who investors hope would show a softer line on the proposed 40 percent tax on resource companies' "super profits", which the industry had been fighting.

And soon after Gillard was sworn in, mining giant BHP Billiton said it would pull a series of anti-tax advertisements following a plea from the new prime minister.

BHP rose 2.0 percent, Rio Tinto was 2.4 percent higher, Fortescue added 3.6 percent and MacArthur Coal lifted five percent.

"There's only one story today," Southern Cross Equities Director Charlie Aitken told Dow Jones Newswires in Sydney.

"The removal of Kevin Rudd as Prime Minister is obviously positive for the Australian equity market, Australian resources and the Australian dollar as it removes a degree of sovereign and regulatory risk."

And Patersons Senior Private Client Adviser, Chris Blair, said: "As you would expect after Rudd's departure, resources stocks are outperforming... Obviously it's giving people some hope that the resources super profits tax will be altered."

Tokyo gained 0.17 percent by the break, Hong Kong added 0.11 percent in the morning and Singapore rose 0.17 percent. Shanghai was the exception, easing 0.14 percent.

Sentiment was subdued, however, after the US central bank suggested after a two-day policy meeting on Wednesday that the eurozone debt crisis was weighing on the economy.

After leaving interest rates at record low levels, the Fed said economic conditions were likely to warrant keeping "exceptionally low" rates "for an extended period," repeating the language used in previous statements.

"The pace of economic recovery is likely to be moderate for a time," said the panel headed by Fed chairman Ben Bernanke.

But it added that "financial conditions have become less supportive of economic growth on balance, largely reflecting developments abroad", likely referring to the eurozone sovereign crisis.

The debt woes of eurozone countries including Greece and Spain have caused concern globally that the problems could spill into other economies and lead to another downturn.

Sentiment was also strained by news that sales of new one-family homes in the United States plunged 32.7 percent month-on-month in May to 300,000. The pace was the slowest since records started in January 1963.

Oil fell, with New York's main contract, light sweet crude for August delivery tumbling 19 cents to $76.16 a barrel. Brent North Sea crude for August delivery eased 20 cents to $76.07 a barrel.

Gold opened at $1,234.00-$1,235.00 an ounce in Hong Kong, down from Wednesday's close of $1,241.00-$1,242.00.