Oil prices fell Wednesday, as concerns about the rapidly spreading coronavirus pandemic and an escalating price war eclipsed pledges by major economies to launch stimulus measures.

Global stock markets sank Wednesday in a third day of wild price swings after President Donald Trump promised aid to get the U.S. economy through the coronavirus outbreak.

London and Frankfurt opened more than 3% lower and Shanghai, Tokyo and Hong Kong all declined. Australia's main index fell 6.4%.

France on Tuesday pledged tens of billions of euros in financial aid and mooted the nationalization of large companies to wage an "economic and financial war" on the coronavirus which has sent most of the country's workforce into lockdown.

Wall Street stocks jumped in late-morning trading Tuesday following fresh emergency actions by the Federal Reserve, rebounding somewhat from Monday's rout.

The White House is proposing a roughly $850 billion economic rescue package Tuesday amid the coronavirus outbreak, a sweeping stimulus for businesses and taxpayers amid unseen since the Great Recession of 2008.

Treasury Secretary Steven Mnuchin planned to outline the package to Senate Republicans at a private lunch, with officials aiming to have Congress approve it this week.

French Finance Minister Bruno Le Maire warned Tuesday the country faced recession this year as he announced a 45-billion euro ($50-billion) aid package to help businesses and employees cope with the coronavirus crisis.

Oil rebounded Tuesday, with investors buying at bargain levels after prices plunged to four-year lows as governments worldwide ramped up measures to contain the spread of the deadly coronavirus.

Leaders of the G7 industrial powerhouses pledged Monday to join forces to halt economic freefall in the wake of the coronavirus pandemic, which they called "a human tragedy."

European automakers began shutting down factories Monday as governments impose confinement and other measures to curtail the coronavirus outbreak, which is expected to take a heavy toll on national economies.

The Bank of Japan on Monday unveiled a series of emergency monetary policy measures to shore up the world's third-largest economy, as the coronavirus pandemic threatens a global recession.