Washington’s NATO allies said they would not get involved in U.S. President Donald Trump’s plan to blockade the Strait of Hormuz, suggesting such measures should only be considered after hostilities end, Reuters reports.

Trump stated that U.S. forces would cooperate with other countries to block all maritime traffic in the Strait of Hormuz after weekend talks failed to produce an agreement to end the conflict with Iran.

Later, the U.S. military clarified that the blockade would apply only to vessels heading to or from Iranian ports.

“The blockade will begin soon. Other countries will join it,” Trump said earlier.

However, NATO allies, including the United Kingdom and France, said they would not be drawn into the conflict by participating in the blockade. Instead, they said they are working on an initiative to keep the strait open, through which about one-fifth of the world’s oil supply passes.