WASHINGTON - US Acting Secretary of Defense Patrick Shanahan said on Tuesday that America's actions so far had been deterring Iran rather than seeking a war. 

"This is about deterrence, not about war. We're not about going to war," the acting Pentagon chief told reporters after attending a briefing at the US Congress.

"Our biggest focus at this point is to prevent Iranian miscalculation, we do not want the situation to escalate," Shanahan added.

Washington and Tehran have been trading words of war over the past two weeks, escalating tension that had been stoked up following America's increasing military buildup in the Middle East citing a threat of Iranian attack.

On Tuesday, senior US officials, including Secretary of State Mike Pompeo, Chairman of the Joint Chiefs of Staff General Joseph Dunford and Shanahan, held the briefing at the Congress, informing the lawmakers about recent developments concerning Iran.

Mike McCaul, the ranking Republican on the House Foreign Affairs Committee, told reporters after attending the briefing that the officials made it clear that the Trump administration has no intention to "go to war in the region".

Over recent weeks, Washington has ratcheted up pressure against Tehran with a series of sanctions, designations and military threats, following Washington's year-long campaign against Iran after the US exit from the landmark Iran nuclear deal in May last year.

Iranian President Hassan Rouhani said on Tuesday that his country will never bow to the pressures exerted by the United States.

Iraqi Prime Minister Adel Abdul Mahdi on Tuesday said that Iraq will send delegations to the United States and Iran to ease the tension in the Middle East.