European stock markets fell and oil prices rose after U.S. President Donald Trump suggested the temporary ceasefire with Iran might be over and that further U.S. strikes were possible.

The Stoxx Europe 600 index closed down 1.7%, marking its third consecutive day of losses and its longest losing streak in a month. More than 80% of the index's constituents declined.

The energy sub-index gained 1.9% as Brent crude oil rose above $80 per barrel following Trump's comments in Ankara. These remarks came hours after the U.S. conducted strikes against Iran and revoked a waiver that had permitted the sale of Iranian oil.

Trump's statements "represent the most significant risk yet of a breakdown in an agreement that has been fraying for weeks," said Violeta Todorova, a senior research analyst at Leverage Shares. "The risk premium that had been steadily receding is likely to come back quickly."

Spain's Ibex 35 index plunged 3.0%, after Trump also threatened to cut off all trade and travel with Spain. Germany's DAX index and France's CAC 40 index also fell by more than 2% each.

"Investors had already given up on the first half of the year but were holding more optimistic hopes for the second half, hoping that period would get us back on track," said Michael Field, chief equity strategist at Morningstar. "Now, we're facing more uncertainty, which is never good for markets."

Europe's benchmark stock index retreated from record highs this week, with investors also pulling money out of some of this year's best-performing stocks, including technology shares. Despite strong earnings expectations for chipmakers, concerns about high valuations are mounting. Meanwhile, consumer-related and defensive stocks, which have significantly underperformed this year, are gaining favor.

"I expect this rotation to continue," said Daniel Murray, deputy chief investment officer at EFG Asset Management. "This doesn't mean tech and AI stocks will crash. We will just see a broadening of market breadth, both geographically and by sector."

Richard Flax, chief investment officer at Moneyfarm, said the rotational trade could persist through the upcoming earnings season. "People will be looking for signals on which areas are relatively strong and which are relatively weak, which will set the tone for how long the rotation out of tech can last," he said.