A major global share index hit its lowest level in a month on Wednesday after US manufacturing activity tumbled to more than a decade low. The manufacturing data sparked worries that the fallout from the US-China trade war is spreading to the world's largest economy. A slowdown in US economic growth would remove one of the few remaining bright spots in the global economy and come just as Europe is seen as close to falling into recession.

The dollar steadied, having earlier been knocked off its highest levels in more than two years following the data. The dollar index - which measures the greenback against a basket of peers - was up 0.16 per cent.

MSCI's gauge of stocks across the globe, covering 49 markets, dipped 0.3 per cent to its lowest since September 5, after shedding 0.83 per cent in the previous session.

European shares opened lower, with London stocks lagging the most on fresh Brexit drama. The pan-European STOXX 600 index was down almost 1 per cent.

The FTSE 100 index slipped 1.5 per cent, the largest drop across European regions and ahead of UK Prime Minister Boris Johnson's talks with Brussels as he prepares to announce his final Brexit offer.

The pound was down 0.6 per cent at $1.2238.

Adding to investor anxieties, European companies looked set for their worst quarterly earnings in three years as revenue drops for the first time since early 2018, according to the latest Refinitiv data.

In Asia, MSCI's ex-Japan Asia-Pacific shares index dropped 0.8 per cent, with Australian shares falling 1.5 per cent and South Korean shares shedding 1.95 per cent. Japan's Nikkei slid 0.5 per cent. China markets are closed for a one-week holiday.

"Our base case is that trade tensions will remain elevated, and we expect global growth to slow in 2020 to its slowest pace since the global financial crisis," said Mark Haefele, chief investment officer at UBS Global Wealth Management.

"We don't rule out a worsening of the trade situation over the next six to 12 months."

Hong Kong's Hang Seng index was down 0.3 per cent after a market holiday the previous day. The index fell as much as 1.2 per cent in early trade. On Tuesday, Hong Kong police shot a teenage protester, the first to be hit by live ammunition in almost four months of unrest in the Chinese-ruled city.

Adding to tensions in Asia, North Korea carried out at least one more projectile launch on Wednesday, a day after it announced it will hold working-level talks with the US at the weekend.

On Wall Street on Tuesday, the S&P 500 lost 1.23 per cent to hit four-week lows. Selling was triggered after the Institute for Supply Management's (ISM) index of factory activity, one of the most closely watched data on US manufacturing, dropped to the lowest level since June 2009.

Markets had been expecting the index to rise back above the 50.0 mark denoting growth.

"Historically, equity returns are worst when the ISM manufacturing drops from levels below the 50 threshold," Patrik Lang, head of equity research at Julius Baer.

"Uncertainty around the US-China trade war is obviously the main reason for the weakness, with companies exposed to global trade increasingly putting off investment decisions."

The data came after euro zone manufacturing data showed the sharpest contraction in almost seven years.

The poor data lifted the Fed funds rate futures price sharply, with the November contract now pricing in about an 80 per cent chance the Federal Reserve will cut interest rates on October 30, compared to just over 50 per cent before the data.

US President Donald Trump once again lashed out at the Federal Reserve on Tuesday, saying the central bank has kept interest rates "too high" and that a strong dollar is hurting American factories.

It is another question, however, whether the US central bank will cut interest rates as hastily as Mr Trump, and financial markets, want.

Just on Tuesday, Chicago Fed President Charles Evans said the Federal Reserve can keep rates steady for now.

Elsewhere in currencies, the yen rose to 107.71 yen per dollar, from Tuesday's low of 108.47.

The euro fell 0.15 per cent to $1.0915.

The Australian dollar fetched $0.6693, having hit a ten-and-a-half-year low of $0.6672 the previous day after the Reserve Bank of Australia cut interest rates and expressed concern about job growth.

Euro zone bond yields inched up after another speech from outgoing ECB chief Mario Draghi calling for fiscal stimulus to boost the region's sluggish economy.

Gold rose to $1,479.13 per ounce from a two-month low of $1,459.50 hit on Tuesday on the back of a robust US dollar.

The weak US data pushed oil prices to near one-month lows, although a surprise drop in US crude inventories helped them to rebound.

Brent crude futures rose 0.2 per cent to $59.01 a barrel, after hitting a four-week low of $58.41 on Tuesday, while US West Texas Intermediate (WTI) crude gained 0.69 per cent to $53.99 per barrel after hitting a one-month low of $53.05.