(Bloomberg) — Oil’s rebound from its biggest crash in a generation ran out of steam on skepticism the U.S. would be able to deliver sufficient stimulus to shield against the fallout from the coronavirus amid a deluge of crude.

Brent crude rose 1.5% in London, paring gains after being up almost 7% in early Asian trading. U.S. President Donald Trump pitched a payroll tax holiday and relief for the travel and hospitality sectors to combat the virus’s impact, while some Republican senators suggested a bailout for the shale industry.

That was after Saudi Arabia upped the ante its oil price war with Russia, pledging to supply a record 12.3 million barrels a day next month in a massive increase to flood the market. Moscow responded within minutes, with Energy Minister Alexander Novak saying Russia had the ability to boost production by 500,000 barrels a day.

The Trump administration’s willingness to revive the economy comes after the disintegration of OPEC+ and subsequent plunge in oil prices threatened the U.S. shale industry and spurred an indiscriminate sell-off in markets already reeling from the coronavirus. However, investor hopes were tempered when the president didn’t appear at a White House briefing Tuesday after promising a day earlier he’d hold a news conference to announce major stimulus.

“The market rally based on Trump’s economic stimulus alone is unlikely to be sustainable” given the amount of crude that will soon be hitting the market, said Howie Lee, an economist at Oversea-Chinese Banking Corp. “Any meaningful rebound will either come from coronavirus fears fading away, or Saudi Arabia and Russia returning to the negotiating table.”

Brent crude for May settlement advanced 1.5% to $37.76 a barrel on the London-based ICE Futures Europe exchange as of 1:52 p.m. in Singapore. It jumped 8.3% Tuesday following a 24% plunge the day before.

West Texas Intermediate crude for April delivery rose 0.6% to $34.55 a barrel on the New York Mercantile Exchange after swinging between a gain of 5.8% and a loss of 2.4%. It rallied 10.4% in the previous session after collapsing by almost 25% on Monday.

Trump spoke with Mohammed bin Salman by phone before the Saudi crown prince escalated the oil-price war Tuesday, according to two people familiar with the call. Russia’s top producer Rosneft PJSC is also planning to ramp up output in April, a person close to the company said. Iraq and Nigeria followed in their wake and said they would increase crude shipments next month.

Meanwhile, the American Petroleum Institute reported that U.S. inventories increased by 6.41 million barrels last week, according to people familiar with the data, highlighting the lack of demand. That would be the seventh straight weekly expansion if confirmed by Energy Information Administration figures due later on Wednesday.

Expectations for a “major” fiscal stimulus package by the U.S. have underpinned sentiment, Stephen Innes, chief Asia market strategist at AxiCorp Ltd., said in a note. But there’s still potential for this to fall through, he said.