HOUSTON — Oil prices are suddenly slumping again, just as American motorists were increasingly feeling the bite.

The price of crude has dropped by 7 percent since a recent high on Tuesday, a result of seemingly coordinated signals from Russian and Saudi officials that they are ready to increase production.

The abrupt reversal interrupted a surge in the American benchmark from less than $50 a barrel last fall to over $70, largely because of the collapse of Venezuelan oil production, the withdrawal of the United States from the Iran nuclear deal and stronger global demand for energy.

But now Russian and OPEC officials appear concerned that the potential for a price spike similar to one a decade ago could spur another drilling frenzy in the United States as well as robust sales of electric cars and other fuel-efficient vehicles.