WASHINGTON -- The Department of Defense announced Monday evening that 1,000 U.S. troops are being sent to the Middle East in response to last week's attacks on oil tankers in the Gulf of Oman, attacks the United States says Iran conducted.

"The recent Iranian attacks validate the reliable, credible intelligence we have received on hostile behavior by Iranian forces and their proxy groups that threaten United States personnel and interests across the region," Acting Defense Secretary Patrick Shanahan said in a statement.

The troops were authorized "for defensive purposes to address air, naval, and ground-based threats in the Middle East," Shanahan also said.

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Last week, the Trump administration accused Tehran of being responsible for an explosion that set two oil tankers on fire off the coast of Iran.

"Iran did do it," Trump said Friday during an interview on Fox News. “It was them that did it.” He also called Iran, "a nation of terror."

In addition, the Pentagon released video last week that officials said show Iran’s Revolutionary Guard removing an unexploded limpet mine from one of the oil tankers targeted near the Strait of Hormuz.

Iran has denied being involved, and instead, has accused the U.S. of waging an “Iranophobic campaign” against it.

Shanahan in his statement said that the request for more troops came from U.S. Central Command, adding that he also consulted with the White House and got advice from the chairman of the Joint Chiefs of Staff, Joseph Dunford.

The United States' relationship with Iran has become strained after Trump pulled out of the 2015 Iran nuclear deal and reimposed sanctions on the country. The U.S. has repeatedly claimed that Iran threatens American forces and facilities in the Middle East.

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However, Shanahan in his statement maintained that "the United States does not seek conflict with Iran."

"The action today is being taken to ensure the safety and welfare of our military personnel working throughout the region and to protect our national interests," he said. "We will continue to monitor the situation diligently and make adjustments to force levels as necessary given intelligence reporting and credible threats."

Contributing: John Bacon, USA TODAY and Associated Press

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This article originally appeared on USA TODAY: Pentagon sending 1,000 U.S. troops to Middle East after oil tanker attacks