Oil prices climbed over 3% to more than $100 a barrel after President Trump rejected an Iranian truce proposal that would have temporarily reopened the Strait of Hormuz. The closure continues to strain global energy supplies.

Higher energy costs are pushing government borrowing costs upward worldwide. Yields on 10-year U.S. Treasury notes rose above 5.2%, extending last week's gains to their highest level since 2007.

Stock-index futures indicate opening losses for U.S. stocks, with markets mixed elsewhere as European shares advanced while Asian markets declined.