Australian shares were on course to snap a two-day losing...

Australian shares were on course to snap a two-day losing streak on Monday, making broad-based gains on firmer commodity prices and optimism around U.S. tax reform.

Top U.S. Republicans said on Sunday they expected Congress to pass a tax code overhaul this week, with a Senate vote as early as Tuesday and President Donald Trump aiming to sign the bill by week's end.

"I think the market is being encouraged by stronger U.S. markets based on the U.S. tax cuts, number one, secondly, by a boost in commodities and material stocks this morning," said Ric Spooner, Chief market strategist at CMC Markets.

The S&P/ASX 200 index (xjo) was up 0.6 percent, or 38.6 points, to 6,035.6 by 0051 GMT. The benchmark slipped 0.2 percent on Friday.

Mining heavyweight BHP Billiton's shares (BHP) rose as much as 1.9 percent to their highest in more than a month tracking strong copper and coal prices.

Copper prices scaled three-week highs on Friday after the New York open and as expectations of strong demand in top consumer China were reinforced by data showing firm industrial activity. [MET/L]

"It is a very big move in recent days and certainly we could go a bit further but I don’t think we are going to see new highs for the year," added CMC Markets' Spooner.

Earlier in the day, the Australian competition watchdog said BHP would sell gas from the Gippsland Basin separately from ExxonMobil's local arm, its joint venture partner.

Mining peer Rio Tinto (RIO) also gained and was trading about 0.8 percent higher. On Friday, iron ore on the Dalian Commodity Exchange DCIOcv1 in key market China rose 1.4 percent to 508 yuan a tonne and coke DCJcv1 jumped 1.7 percent to 2,056 yuan.

Aconex Limited (ACX), a provider of cloud solutions to the construction industry, zoomed as much as 44.7 percent, its most in more than two years as software giant Oracle Corp made a bid for it.

Elsewhere in the mining sector, Indian firm Adani cancelled plans with Downer EDI Ltd (DOW) to help develop and run its Carmichael coal mine in Australia, leading to the transport service provider's stock falling as much as 1.7 percent.

Among financials, Australia and New Zealand Banking Group Limited (ANZ) pushed the sectoral index .AXFJ by its most in 10 days after it announced a A$1.5 billion share buy-back following the sale of its 20 percent stake in Shanghai Rural Commercial Bank . The lender's shares rose to their highest in over three months.

Across the Tasman Sea, New Zealand's benchmark S&P/NZX 50 index (nz50) slipped 0.1 percent, or 11.13 points, to 8,349.73 as utility stocks weighed on the benchmark.

Contact Energy (CEN) was the benchmark's main drag, falling as much as 2.3 percent after it reported sales figures for November which fell year-on-year.