"We have gone back to a turbo-charged version of the great financial crisis," said Simon Fennell, a portfolio manager in William Blair's global equity team, referring to how markets have surged on mass central bank and government stimulus.
"Today we will also see if the ECB is going to go to 1 trillion or beyond with its PEPP programme," he added, a reference to the central bank's beefed-up emergency bond buying scheme.
A 1.4% rise in MSCI's broadest index of Asia-Pacific shares, excluding Japan, kept it tracking towards a weekly gain of more than 5%, its best in three weeks.
Optimism was also driven by Wall Street's strong finish on Wednesday after partial results from a trial of Gilead's antiviral drug remdesivir, suggested it could help speed recovery from COVID-19, the respiratory disease caused by the new coronavirus.
Japan's Nikkei .N225 jumped 2.15% to a seven-week high and Australia's ASX 200 rose 2.4%, with the mood further supported by South Korea reporting no new domestic coronavirus cases for the first time since its Feb. 29 peak.
More caution was evident in other asset classes, with the U.S. dollar steady against most of the other major currencies /FRX and German Bund yields - which move inversely to prices - dipping to a one-month low ahead of the expected ECB moves.
"It's a hope-based rally rather than an evidence-based rally," said Anthony Doyle, cross-asset specialist at fund manager Fidelity International in Sydney.
There were still worries about a second wave of infections, he said, adding that huge piles of cash waiting to go back into the markets suggest investor confidence remained nervy.
HEY BIG SPENDERS
It's not only equity markets that have rebounded sharply this month. Gold is set for its best month in four years and copper, which is seen as a something of bellwether of global industry, was on track for its best performance since December 2017.
Markets have been excited by the prospect of a COVID-19 treatment because it may help economies emerge from lockdowns.
Partial results from the 1,063-patient U.S. government trial of Gilead's remdesivir were hailed as "highly significant" by the top U.S. infectious disease official, Anthony Fauci.
They showed hospitalised COVID-19 patients given the drug recovered in 11 days, compared with 15 days for patients given a placebo, and a slightly lower death rate.
But since treatment hopes don't seem to take into account regulatory and distribution difficulties, should a treatment be found, currency and bond markets were more circumspect.
"Any positive medical development is helpful," said Westpac FX analyst Sean Callow. "But no-one should be counting on a major breakthrough - the key for markets is control of the spread of the virus."
The yield on benchmark U.S. 10-year Treasuries dipped to 0.6075 % meanwhile, after the U.S. Federal Reserve left interest rates near zero and gave no indication of lifting them any time soon.
BlackRock’s Chief Investment Officer of Global Fixed Income, Rick Rieder, who oversees $2.2 trillion of assets, said it showed the Fed was committed to doing "whatever it takes".
Blackrock expects the U.S. central bank to purchase the equivalent of at least $1.5 trillion in Treasuries over the remainder of the year. Along with other crisis-fighting measures its balance sheet will balloon by $7 trillion, or $26 billion per day.
"The magnitude of the policy response to this economic crisis is simply stunning," Rieder added.
With all that to digest, the dollar held its ground against the resurgent Australian dollar for the first time in a week and barely budged against the euro which was at $1.0875 as the ECB's 1145 GMT statement and 1230 GMT news conference loomed.
Gold was a touch higher at $1,715 per ounce and things were still wild in oil markets. Brent crude and U.S. crude futures rose $2.1 and $2.4 - or 11.8% and 16.2% a barrel - respectively amid optimism that a storage squeeze is not as bad as first feared, and that demand for fuel may soon return.
(Additional Reporting by Tom Westbrook in Singapore and Swati Pandey in Sydney; Editing by Alex Richardson, Kirsten Donovan) ((firstname.lastname@example.org; +44 (0)207 542 9033; Reuters Messaging: email@example.com Twitter @marcjonesrtrs))
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