WASHINGTON, May 29, (AP): Financial markets welcomed a U.S. court ruling that blocks President Donald Trump from imposing sweeping tariffs on imports under an emergency-powers law. US futures jumped early Thursday and oil prices rose more than $1. The US dollar rose against the yen and euro. The court found the 1977 International Emergency Economic Powers Act, which Trump has cited as his basis for ordering massive increases in import duties, does not authorize the use of tariffs.

The White House immediately appealed and it was unclear if Trump would abide by the ruling in the interim. The long term outcome of legal disputes over tariffs remains uncertain. But investors appeared to take heart after the months of turmoil brought on by Trump's trade war. The future for the S&P 500 was up 1.5% while that for the Dow Jones Industrial Average gained 1.2%. In early European trading, Germany's DAX gained 0.5% to 24,160.75.

The CAC 40 in Paris jumped 0.9% to 7,860.67. Britain's FTSE was nearly unchanged at 8,722.63. Japan’s Nikkei 225 index jumped 1.9% to 38,432.98. American’s largest ally in Asia has been appealing to Trump to cancel the tariffs he has ordered on imports from Japan and to also stop 25% tariffs on steel, aluminum and autos.

The ruling also pushed the dollar sharply higher against the Japanese yen. It was trading at 145.40 yen early Thursday, up from 144.87 yen late Wednesday. A three-judge panel ruled on several lawsuits arguing Trump exceeded his authority, casting doubt on trade policies that have jolted global financial markets, frustrated trade partners and raised uncertainty over the outlook for inflation and the global economy.

Many of Trump's double-digit tariff hikes are paused for up to 90 days to allow time for trade negotiations, but the uncertainty they cast over global commerce has stymied businesses and left consumers wary about what lies ahead. "Just when traders thought they’d seen every twist in the tariff saga, the gavel dropped like a lightning bolt over the Pacific,” Stephen Innes of SPI Asset Management said in a commentary. The ruling was, at the least, "a brief respite before the next thunderclap,” he said. Elsewhere in Asia, Hong Kong's Hang Seng added 1.3% to 23,561.86, while the Shanghai Composite index gained 0.7% to 3,363.45.