London, Oct 2 (AFP) Stock markets tumbled Wednesday as worse-than-expected US data revived worries about the impact of the US-China trade war on the global economy.

London was additionally hit as Prime Minister Boris Johnson unveiled his take-it-or-leave-it Brexit plan, with many fearing it will lead to a costly and messy no-deal British departure from the EU at the end of the month.

Asian markets were weaker overnight, hit by news that US manufacturing activity fell to its lowest level since June 2009.

New York, after losses Tuesday, opened down on that lead and then slumped further after a report showed hiring slowed sharply in September while a blockbuster jobs increase reported for August was also revised down.

The data showed "the job market has shown signs of a slowdown," said Ahu Yildirmaz, vice president and co-head of the ADP Research Institute.

The figures came ahead of the all-important government employment report due Friday as dealers look for signals on the US Federal Reserve's interest rate plans, while the corporate earning season is also about to get underway.

The Institute for Supply Management (ISM) pointed to trade conflicts as the biggest headwind facing the US economy.

"Equities are in full retreat," said Chris Beauchamp, chief market analyst at financial spread-betting firm IG.

"The risk-off atmosphere created by yesterday's US ISM miss continues to hang over markets.

"European equities have turned firmly lower in early trading on the very reasonable assumption that, if things are that bad for the US, then they must be even worse for Europe."

The ISM data pointed to the impact of the China-US trade war and could put pressure on US President Donald Trump to push through an agreement with Beijing. Top-level talks are planned for later this month.

Adding to the selling pressure in Asia were long-running concerns about the impact of increasingly violent pro-democracy protests in Hong Kong that saw a demonstrator shot and wounded by police on Tuesday.

Hong Kong stocks fell 0.2 percent -- coming off earlier steep losses -- as investors returned from a public holiday to mark China's National Day which saw some of the worst violence in the city since protests began in June.

Tokyo ended 0.5 percent lower, Sydney fell 1.5 percent and Singapore lost 1.2 percent. Shanghai was closed for a holiday.

Seoul shed almost two percent after North Korea fired a missile into the sea just a day after Pyongyang said it would resume stalled nuclear talks this week. (AFP)

(This is an unedited and auto-generated story from Syndicated News feed, LatestLY Staff may not have modified or edited the content body)