Australia has agreed to a request from the United States to join a coalition of countries protecting oil tankers and cargo ships from threats posed by Iran in the Strait of Hormuz, Prime Minister Scott Morrison said Wednesday.

Australia becomes the third country to join the coalition after Britain and Bahrain. Washington has since July called on around 60 countries including Japan to join its operation to secure the narrow waterway, one of the most volatile transit routes for the world's oil supply.

"This destabilizing behavior is a threat to Australia's interests in the region," Morrison told a news conference.

(Satellite image of the Strait of Hormuz on 24 May, 2017.)[Gallo Images/Getty]

The prime minister described Canberra's intended contribution of a maritime surveillance aircraft and a Royal Australian Navy frigate as "modest, meaningful, and time limited."

Australia's decision to join the coalition comes after Canberra and Washington held "two-plus-two" security talks of defense and foreign ministers earlier this month.

At the time Australia was still undecided on joining, despite U.S. Secretary of State Mike Pompeo describing the situation in the Strait of Hormuz as one of the "most pressing foreign policy challenges of our time."

Iran has been blamed for attacks on two oil tankers -- one of them operated by a Japanese shipping firm -- in June. Last month Iran's Islamic Revolutionary Guard Corps seized a British-flagged oil tanker.

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