The U.K. Conservative prime minister also said the he would work with allies to “de-escalate” Middle East tensions that have soared since the Sept. 14 attack on the world’s largest oil processor and an oil field.

Iranian Foreign Minister Mohammad Javad Zarif, who is in New York for the U.N. meetings, has warned that any retaliatory strike on Iran by the U.S. or Saudi Arabia will result in ``an all-out war.''

Saudi Arabia said drones attacked one of its oil pipelines as other assaults targeted energy infrastructure elsewhere in the kingdom on Tuesday