U.S. President Donald Trump discussed how to mitigate the impact of a possible monthslong U.S. blockade of Iran's ports with oil companies, a White House official said on Wednesday, as the U.S. renewed its calls for other nations to help open the Strait of Hormuz.

Tuesday's talks with oil executives followed a deadlock in efforts to resolve the conflict, which has led the United States to try to squeeze Iran's oil exports with a naval blockade aimed at forcing it to reopen the strait to shipping.

As Washington and Tehran traded public threats, mediator Pakistan was trying to avoid an escalation while the ?two sides exchange messages on a potential deal, a Pakistani source said on Wednesday.