HONG KONG (AP) — World shares traded lower and oil prices rose back to around $100 per barrel on Thursday as a de-escalation of the Iran war remained uncertain.

U.S. futures were down 0.6%.

In early European trading, Britain’s FTSE 100 lost 1.3% to 9,977.65. France’s CAC 40 fell 1.1% to 7,762.41, and Germany’s DAX dropped 1.6% to 22,583.07.

In Asia, Tokyo’s Nikkei 225 closed 0.3% lower at 53,603.65. South Korea’s Kospi lost 3.2% to 5,460.46.

Hong Kong’s Hang Seng fell 1.9% to 24,856.43, while the Shanghai Composite index was down 1.1% to 3,889.08.

Australia’s S&P/ASX 200 edged down 0.1%, while Taiwan’s Taiex was trading 0.3% lower.

Oil prices were up again on Thursday. Brent crude, the international standard, rose 3.2% to $100.39 per barrel. It was below $95 on Wednesday. Benchmark U.S. crude was 3.5% higher at $93.44 a barrel.

The rise in oil prices came as Tehran on Wednesday dismissed a ceasefire plan by the U.S., after the administration of U.S. President Donald Trump offered a 15-point proposal to Iran and Trump this week delayed a self-imposed deadline to “obliterate” its power plants in order to force Iran to reopen the Strait of Hormuz.

Trump insisted late Wednesday that Iran is still negotiating following its rejection of the U.S.’s ceasefire proposal.

Iran also launched more attacks on Israel and Gulf Arab countries as Israel launched airstrikes on Tehran and the U.S. prepared to deploy more American troops to the region.

With the Strait of Hormuz, a crucial waterway between Iran and Oman where roughly a fifth of the world’s oil typically passes through, remaining largely closed after the Iran war began, oil prices have fluctuated, climbing around 40% since the beginning of the war, which is now in its fourth week.

On Wednesday, Wall Street stocks closed higher. The S&P 500 gained 0.5% to 6,591.90. The Dow Jones Industrial Average climbed 0.7% to 46,429.49, and the Nasdaq composite rose 0.8% to 21,929.83.

U.S.-listed shares of Arm Holdings jumped 16.4%, following an announcement by the U.K. company that it would be launching and selling its own chips which is expected to drive future revenue.

On Holding, the Swiss sportswear company selling On running shoes, fell 11.2% in the U.S. Its CEO Martin Hoffmann is stepping down and the company has named two co-founders as co-CEOs.

In other dealings early Thursday, gold and silver prices fell. Gold prices dropped 2.9% to $4,420.80 per ounce. Silver prices lost 6.6% to $67.85 an ounce.

The U.S. dollar rose to 159.52 Japanese yen from 159.47 yen. The euro was at $1.1557, down from $1.1559.

Chan Ho-him, The Associated Press