Gov. Mikie Sherrill sent letters on Monday to 12 New Jersey port operators, warning them to turn away Russian diesel tankers. She said she would use every available legal tool to block fuel offloading. This move challenges President Trump, who recently lifted the ban on importing Russian diesel fuel shipments.

Gov. Mikie Sherrill sent a letter to 12 port and terminal operators in the state, warning them they "could be subject to millions of dollars in penalties" long after President Trump leaves office.

Gov. Mikie Sherrill sent letters on Monday to a dozen port and terminal operators in New Jersey, warning them to "turn away" any tanker carrying Russian diesel or face what she called harsh penalties.

Ms. Sherrill, a Democrat, said that accepting the fuel would violate federal law and that she was prepared to use "every available legal and regulatory tool" to block any tanker from offloading Russian fuel in New Jersey.

It is unclear if any Russian fuel is headed toward New Jersey, but Ms. Sherrill's position could put the state on a collision course with President Trump, who last month lifted a ban on the import of Russian diesel as part of his efforts to bring down the cost of the fuel. Gasoline and diesel prices have risen since the United States and Israel attacked Iran at the end of February.

A Russian official has said that three tankers carrying diesel were en route to the United States, but it is not clear how many vessels are actually involved, or where they might be headed.

The owners of the diesel-importing facilities, some of which belong to large oil companies, would be forced to choose sides. Senator Richard Blumenthal of Connecticut, a Democratic member of the Senate Armed Services Committee, has also demanded that two shipping companies recall tankers "carrying illegal Russian diesel."

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A White House spokeswoman did not immediately respond to a request for comment on Ms. Sherrill's warning.

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