WASHINGTON — In the wake of an attack on two oil tankers in the Gulf of Oman, Iranian military fast-boats prevented privately owned tug boats from salvaging one of the damaged vessels, two U.S. officials aware of the situation told CNBC. The latest conflict from the world's most important oil choke point brought oil prices up about 1% on Friday and as much as 4% the day prior on renewed fears of conflict in the Middle East leading to global oil supply disruptions. America's top diplomat, Secretary of State Mike Pompeo, blamed Iran for Thursday's attacks without citing specific evidence as to why Tehran was responsible. "Iran is lashing out because the regime wants our successful maximum pressure campaign lifted," Pompeo said Thursday. "No economic sanctions entitle the Islamic Republic to attack innocent civilians, disrupt global oil markets and engage in nuclear blackmail."

Iranian Revolutionary Guards drive speedboats in front of an oil tanker at the port of Bandar Abbas Atta Kenare | AFP | Getty Images

President Donald Trump said Friday that if Iran were to block the Strait of Hormuz, "it's not going to be closed for long," but did not elaborate on what potential steps the U.S. would take in response. "They're not going to be closing [the strait]," Trump reiterated during a telephone interview with Fox News. Earlier this year, Iran threatened to close the strait in response to a U.S. decision to end waivers on reimposed sanctions for companies that export oil from Iran. The Strait of Hormuz is a gateway for almost a third of all seaborne crude oil. In an exclusive interview with CNBC on Friday, Trump's energy secretary called Iran the "bad neighbor in the neighborhood." "Iran should be thinking about how do we maintain our market share, how do we act like good neighbors, how do we continue to be a part of the global community instead of these obvious acts of treachery in the Strait of Hormuz," Energy Secretary Rick Perry said. At the Pentagon, acting Secretary of Defense Pat Shanahan called the matter an "international problem," adding that his role would be to "set the conditions for diplomacy." He added that he was in close coordination with U.S. Central Command to verify whether forces in the region had necessary resources and support for their missions. In a statement Friday, the board of directors for Frontline Ltd. said that all 23 crew members of the Front Altair oil tanker were unharmed and that the cause of the explosion is unknown. "The incident will be thoroughly investigated by the Company along with third parties, including governmental officials, to determine the cause," the statement said.