SYDNEY: Asian markets were slightly weaker on Wednesday even though US stocks touched new highs, as oil prices rose with a storm heading for the Gulf of Mexico and tensions escalating between Saudi Arabia and Yemen's Iran-backed Houthis.

In Asia, MSCI's broadest index of Asia-Pacific shares excluding Japan was down 0.3% after US stocks ended higher. The index is up 1.5% so far this month.

The S&P 500 hit a fresh record on Tuesday, up about 0.6% on the day, while the tech-heavy Nasdaq gained 0.45%, also an all-time high. The Dow Jones Industrial Average rose 0.5%.

In Asian trading, US crude ticked up 1.05% to $90.38 a barrel; prices were little changed in the international session. Brent crude rose 1.06% to $101.65 per barrel.

The price rise came as commodity investors weighed supply constraints from a storm heading for North American oil-producing regions and Houthi attacks on Saudi Arabia against increased supplies of Middle East crude.

Around ​12 million barrels per day (bpd) of crude oil and 2 million bpd of refined products have left the Middle East on tankers in the last 7 to 10 days, commodities trading giant Vitol's CEO Russell Hardy said on Tuesday.

The positive sentiment among traders of US equities followed a stabilisation in global bond yields overnight.

Heavily sold French debt pulled back on Tuesday as far-right presidential candidate Marine Le Pen pledged spending cuts and a reduction in the country's budget deficit.

Ten-year French yields fell more than 11 basis points and the spread between French OATs and German bunds , which hit almost 160 bps last week, according to LSEG data, narrowed to 132 bps.

"The magnitude of the move is striking given the 2027 election remains several months away and France's deteriorating fiscal dynamics are hardly new," said Laura Cooper, Nuveen's head of macro credit and global investment strategist.

"What has changed is sharply higher yields, leaving investors less willing to look through those vulnerabilities."

That decline helped the euro make a small recovery and stabilise just above $1.1250.

"A sense of calm returned to European bond markets with French, Italian and Greek bonds outperforming amid a broad rally," ANZ economists wrote in a note.

Ten-year US Treasuries rose back to 5.3% in Asian morning trade.

Longer-term US yields were edging higher on Wednesday ahead of a 10-year auction later in the session and a 30-year auction on Thursday. The auctions will show the depth of investor demand for US debt, analysts said. US longer-dated yields hit a 24-year high on Monday amid a persistent selloff since late August due to inflation and debt concerns.

Australian shares were flat on Wednesday, while Japan's Nikkei stock index was off 0.86%.

Hong Kong's Hang Seng Index was down 0.63% in early trading, dragged lower by a 4% decline in the index's biotech index. Mainland China's financial markets remained closed for a holiday.

The dollar index, which measures the greenback against a basket of currencies, rose 0.03% to 101.94 following a 0.27% slide in the prior session.

The Japanese yen weakened 0.19% to 158.43 per dollar. Sterling dipped 0.08% to $1.3262.

A stabilisation in oil prices in the US trading session, the euro's slight recovery and US Treasury bond yield shifts put pressure on the dollar, CBA analysts said.

The Federal Reserve on Wednesday will publish the minutes of its September 15 and 16 policy meeting, which will be scrutinised for potential rate moves over the next few months.

Traders scaled back expectations of a Fed rate increase this month to 19% from about 50% a week earlier.

Spot gold was recently higher at $4165.53 per ounce. - Reuters