Stocks hold gains ahead of inflation test

World stocks have held on to modest gains on cautious optimism that United States data will confirm inflation is softening, while the yen rose with a report Japan will this month review the side-effects of its ultra-easy policy.

An MSCI gauge of world stocks rose 0.2 per cent to a four-week high by 0831 GMT ahead of core US consumer price inflation, which is expected to have slowed to an annual 5.7 per cent in December, from 6 per cent a month earlier.

Month-on-month headline inflation is seen at zero.

Bonds held gains, also mirroring hopes of a softer inflation print, and the US dollar was near a seven-month low against a basket of currencies.

Europe's STOXX 600 equity benchmark index rose 0.4 per cent to its highest since April 2022.

The data due at 1330 GMT is set to have a big impact on markets by shaping expectations of the speed of interest rate hikes in the world's biggest economy.

Markets have priced better-than-even odds that the Federal Reserve raises rates by 25 basis points, rather than 50, at February's meeting.

"Both the worst and best days for the S&P 500 in 2022 came on days of a CPI release. As such, it's inevitable that today's US CPI has the ability to shape the next month," Deutsche Bank strategist Jim Reid wrote.

"The latest releases have seen two downside surprises on CPI in a row for the first time since the pandemic, which has led to growing hopes that the Fed might achieve a soft landing after all," he added.

The MSCI's broadest index of Asia-Pacific shares outside Japan rose 0.1 per cent after climbing to a seven-month high, while Japan's Nikkei was steady.

S&P 500 futures were broadly steady following gains for Wall Street indexes on Wednesday.

Boston Federal Reserve bank leader Susan Collins told the New York Times she was leaning towards a 25 basis point hike.

Optimism for a more benign rates outlook and a pickup in demand as China emerges from strict COVID-19 restrictions kept oil prices near one-week peaks.

Brent crude futures topped $US83 ($A120) on Thursday before retreating slightly to trade flat on the day at $US82.67 ($A119.50) a barrel.

US Treasuries added a little to Wednesday's gains, sending benchmark 10-year yields down 4.4 basis points (bps) to 3.514 per cent.

German 10-year yields, the benchmark for the euro zone, fell 7.0 bps to 3.509 per cent.

Along with hopes that Western central banks will be gentler, investors are also banking on a recovery in China to help global growth and are eyeing a potential policy shift in Japan.

The Bank of Japan stunned markets last month by widening the band around its 10-year bond yield target, a move that triggered a sudden rise in yields and a jump in the yen.

On Thursday, Japan's Yomiuri newspaper reported the BOJ will review the side effects of Japan's ultra-easy settings sooner than expected - at next week's policy meetings - and that it might take additional steps to correct distortions in the yield curve.

The yen rose as much as 0.9 per cent and was last at 131.75 per dollar.

Ten-year Japanese government bond futures fell to almost eight-year lows.

Foreign exchange markets elsewhere were holding their breath ahead of the US CPI data while China's reopening kept a bid under Asia's currencies.

The dollar index added 0.1 per cent to 103.23, not far off a seven-month low of 102.93 hit this week.

The yuan traded near five-month highs at 6.7555 per dollar.

China on Thursday reported consumer price falls in December and a larger-than-expected drop in factory gate prices - underscoring weakness in demand - which investors are betting will recover in the coming months.

"It's not enough for China to come out of COVID to really turn the whole world economy around," said Steven Wieting, chief investment strategist and chief economist at Citi Global Wealth Investments.

"But it really weighs in the opposite direction."