Washington anticipates the "period of uncertainty" to hang over the gulf indefinitely, Admiral John Richardson, the service's chief of naval operations, told Reuters aboard a military aircraft.
"It is a period of uncertainty that we are entering into, right — how the whole world will respond to this latest development," Richardson told reporters.
The US Navy has to "remain alert, I mean, even a little bit more alert than usual, to just be open to any kind of response or new development or something like that," the admiral added.
The US Navy's primary base in the Middle East is located on the island nation of Bahrain, where the Fifth Fleet is stationed. Washington leased space at the naval port from London starting in 1950, about 15 years after the British Royal Navy established their base, the HMS Jufair, there.
The US assumed full occupancy of the base in 1971 after Bahrain achieved independence from Britain. Last month, the British Royal Navy opened a permanent base in Bahrain, the first establishment of an overseas military base by the country in 50 years, the Telegraph reported.
On May 8, the American president announced that the US would no longer abide by the terms of the multilateral deal that allowed inspectors from the International Atomic Energy Agency to look at Iran's suspected dual-use nuclear infrastructure in exchange for lifting economic sanctions.
The 2015 Iran nuclear deal, signed by Russia, China, France, the US, the United Kingdom, Germany ("the P5+1 countries") and Iran, worked. The South Asian Shia-majority nation has not materially broken its commitments under the deal, according to international inspectors, while commercial ties between Iran and Western partners like France and Germany have flourished.
In March, three years after the agreement was signed, IAEA Director Yukiya Amano announced that the agency's inspectors verified that Iran was not in violation of the agreement.