BP PLC (BP) said Wednesday it was taking steps to shut down a natural-gas field in the U.K. North Sea that it jointly owns with Iran, confirming a warning last month that new European sanctions could interrupt the operation.

Last month, the European Union approved new sanctions, including a ban on joint energy investments by Iranian and Western companies among other things, in a bid to bring
Iran to the negotiating table over its nuclear program.

Iran has since proposed new dates to return to talks with major powers.

A spokesman for BP said "preparations are under way" for the shut down of the field, adding it would take "several days" to suspend the operations.

"We are still seeking clarification" from the
U.K. government on how the sanctions apply to the field, he said.