Industry sources told AFP Trump was planning to delay imposing tariffs on EU auto imports while the US pursues agreements with key trading partners.
European and US markets that had been in negative territory earlier in the day suddenly jumped higher, with German auto manufacturers among those who stood to benefit.
"Whether or not the news will be confirmed remains to be seen. Traders are buying European car shares" meanwhile, remarked Fawad Razaqzada at Forex.com.
Asian equity markets had already surged higher in the wake of strong gains elsewhere on Tuesday.
The dollar was mixed against main rivals, with the euro limiting its loss thanks to data that showed a rebound in first quarter German growth.
Although stock markets have been whipsawed by Trump tweets and the twists and turns of Chinese-US trade talks, they "still exhibit hope that we could see some form of resolution emerge from this current standoff," noted Joshua Mahony, senior market analyst at IG trading group.
After more than doubling tariffs on $200 billion of Chinese goods last week -- sparking retaliation from Beijing -- Trump has threatened to impose a further $300 billion if China does not give ground in the high-stakes talks.
He then gave markets some hope that a deal between the economic titans would eventually be struck.
Shanghai's main stocks index ended 1.9 percent higher and Hong Kong put on 0.5 percent Wednesday.
Saudi Arabia, the world's top crude exporter, on Wednesday said that attacks on two of its tankers and a major pipeline targeted the security of global oil supplies.
Drone attacks claimed by Iran-aligned Yemeni rebels shut down one of the kingdom's main oil pipelines on Tuesday, further ratcheting up Gulf tensions after the mysterious weekend sabotage of four ships, two of them Saudi tankers.
London - FTSE 100: UP 0.8 percent at 7,296.95 points (close) Frankfurt - DAX 30: UP 0.9 percent at 12,099.57 (close) Paris - CAC 40: UP 0.6 percent at 5,374.26 (close) EURO STOXX 50 - UP 0.6 percent at 3,385.78 (close) Tokyo - Nikkei 225: UP 0.6 percent at 21,188.56 (close) Hong Kong - Hang Seng: UP 0.5 percent at 28,268.71 (close) Shanghai - Composite: UP 1.9 percent at 2,938.68 (close) New York - Dow: UP 0.5 percent at 25,660.05 Euro/dollar: DOWN at $1.1207 from $1.1208 at 2040 GMT Pound/dollar: DOWN at $1.2876 from $1.2907 Dollar/yen: DOWN at 109.57 yen from 109.62 yen Oil - Brent Crude: UP 78 cents at $72.02 per barrel Oil - West Texas Intermediate: UP 27 cents at $62.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)