After the downing of a U.S. surveillance drone on Thursday, President Donald Trump first approved military strikes against Iran but later in the day cancelled their launch, The New York Times reports.

In a day of rising tensions and a flurry of meetings in Washington, the U.S. president apparently decided to hold back military action, many knowledgeable sources told the Times.

Trump who earlier in the day said Iran had made a "bad mistake" by attacking the U.S. aircraft, surprised observers later by saying the Iranian action was perhaps not deliberate. This was seen as an indication that he wanted to maintain flexibility in deciding how to respond to Iran's defiance.

The Times report says that the operation was almost underway when Trump decided to step back.

Since the administration dispatched an aircraft carrier group to the Persian Gulf to deter any Iranian threats on its interests, oil tankers have come under mysterious attacks, which Washington and its allies in the region have blamed on Iran.

The latest attack on a drone puts Trump in a tough situation of being pressured to show resolve, after many warnings issues by his administration for Tehran to refrain from any provocation.