The U.S. on Thursday imposed sanctions on a network of more than a dozen people and firms that are accused of facilitating the shipment of millions of barrels of Iranian oil to China.

The U.S. Treasury said on Thursday it is imposing new sanctions on individuals and tankers helping to ship millions of barrels of Iranian crude oil per year to China. The move comes after U.S. President Donald Trump earlier this week vowed to bring Iran's oil exports to zero as the U.

The Treasury Department Thursday imposed new sanctions on an international oil network it said ships hundreds of millions of dollars of oil to China. The funds allegedly benefit Iran's military.

Trump also directed his U.N. ambassador to work with allies to "complete the snapback of international sanctions and restrictions on Iran," under a 2015 deal between Iran and key world powers that lifted sanctions on Tehran in return for restrictions on its nuclear program.

President Donald Trump’s recent decision to reinstate a goal from his first presidency to bring Iran’s oil exports to zero has had little impact on crude prices so far.