Global stock markets got a shot in the arm from hopes for a coronavirus vaccine on Wednesday, with the outlook for more US financial stimulus adding to the brighter mood.

Optimism was sparked by American biotech firm Moderna saying the final stage of human trials for a COVID-19 vaccine would start at the end of the month, after a report said first stage tests had been a success.

The news follows an announcement from Pfizer and BioNTech that two of four candidates for treatment had received "Fast Track" designation from US officials.

"It goes without saying that a vaccine will be the gamechanger in the pandemic, the thing that will allow life to return to normal and businesses and households to thrive once again," said Craig Erlam, analyst at the Oanda trading group.

"So it's hardly surprising that investors get a little excited when the results of these trials emerge, even those in the early stages."

European markets were as much as two percent higher at the close, while US indices won moderate gains. The S&P 500 finished up 0.9 percent.

Providing added support were signs that the US might add to its stimulus after reports said top Republicans were reconsidering their opposition to it.

Trillions of dollars pledged by the US and other governments and central banks around the world have been a key driver of the rally in stock markets from their March lows -- but one that is weighing on the US currency.

Strong US industrial output numbers released shortly before the New York opening bell added to the better mood on trading floors.

On the corporate front, Apple shares rose after a European court handed the company a big win against the EU Commission, cancelling an order for Apple to repay Ireland 13 billion euros ($15 billion) in back taxes.

Goldman Sachs shares were up after the bank beat earnings forecasts, a day after JPMorgan Chase also outperformed expectations.

Oil prices rose, defying doubts about OPEC's willingness to maintain all its recent production cuts for much longer and finishing at their highest level in four months.

Analysts attributed part of the price rise to a sharp drawdown in US inventories, but said crude was also carried along by renewed confidence in the economic outlook.

China said it will retaliate after Donald Trump signed off on a bill authorising sanctions on banks over China's clampdown in Hong Kong
China said it will retaliate after Donald Trump signed off on a bill authorising sanctions on banks over China's clampdown in Hong Kong AFP / JIM WATSON

"Crude prices have risen along with other risk assets, such as stocks and copper," said Fawad Razaqzada at ThinkMarkets.

"Thus, some of their gains are entirely due to the ongoing risk-on rally," he said, adding that prices appeared to be "fairly balanced" at current levels.

New York - Dow: UP 0.9 percent at 26,870.10 (close)

New York - S&P 500: UP 0.9 percent at 3,226.56 (close)

New York - Nasdaq: UP 0.6 percent at 10,550.49 (close)

London - FTSE 100: UP 1.8 percent at 6,292.65 points (close)

Frankfurt - DAX 30: UP 1.8 percent at 12,930.98 (close)

Paris - CAC 40: UP 2.0 percent at 5,108.98 (close)

EURO STOXX 50: UP 1.7 percent at 3,378.21 (close)

Tokyo - Nikkei 225: UP 1.6 percent at 22,945.50 (close)

Hong Kong - Hang Seng: FLAT at 24,481.58 (close)

Shanghai - Composite: DOWN 1.6 percent at 3,361.30 (close)

West Texas Intermediate: UP 2.3 percent at $41.20 per barrel

Brent North Sea crude: UP 2.1 percent at $43.79 per barrel

Euro/dollar: UP at $1.1410 from $1.1400 at 2100 GMT

Dollar/yen: DOWN at 106.92 yen from 107.24

Pound/dollar: UP at $1.2589 from $1.2553

Coronavirus Pfizer OPEC