The US military has been ordered to be ready for possible strikes against Iran, according to fresh reports. President Donald Trump is said to be weighing the timing, with action possible before the November 3 midterm elections. No decision has been made.

The news rattled markets on Thursday. Oil prices jumped more than 3% on fears that a new conflict could hurt energy supplies. European shares fell, with the STOXX 600 index down 0.9% to 624.24. US stock futures were lower too. The Dow was down 1%, while the S&P 500 and Nasdaq dropped from record highs hit on Tuesday.

Investors moved money into safe assets. Gold futures rose to about $4,136 an ounce. Bitcoin fell to around $82,500. The yield on the 10-year US Treasury bond rose to about 5.35%, its highest since 2002.

The reports come as the seven-month conflict between the US, Israel, and Iran continues to simmer. Energy and bank stocks fell as traders weighed the risk of a wider war.

Fed minutes released this week showed officials divided over further interest rate hikes. Wall Street will watch closely in the coming days for any sign of what the White House decides next.