UK foreign minister stresses 'urgent need' to reopen Hormuz strait
Cooper said Iran's "recklessness" in blockading the waterway was "hitting our global economic security" as she kicked off the virtual meeting of international allies from London.
The strait has been virtually closed since the US-Israeli war against Iran started on February 28, impacting global supplies of important commodities including oil, liquid natural gas, and fertiliser.
That has led to a sharp rise in energy prices.
Cooper said foreign ministers and representatives from more than 40 countries had joined the call to discuss "the urgent need to restore freedom of navigation for international shipping, and the strength of our international determination to see the Strait reopen once more".
A total of 37 countries have signed a statement, first published last month, expressing "readiness to contribute to appropriate efforts to ensure safe passage through" the shipping lane.
Britain, France, Germany, Italy, Japan and the Netherlands are among those to have signed it.
The United States, China, and most Middle Eastern countries have not, according to a list provided by the UK government.
"We have seen Iran hijack an international shipping route to hold the global economy hostage," Cooper added in her opening remarks, which were broadcast by media before the rest of the meeting took place behind closed doors.
Cooper said the discussions would focus on the "collective mobilisation of our full range of diplomatic and economic tools and pressures" to "enable a safe and sustained opening of the Strait".
The meeting comes after US President Donald Trump urged oil-importing nations to show "courage" and seize the Strait of Hormuz.
"The countries of the world that... receive oil through the Hormuz Strait must take care of that passage," Trump said in a prime-time address at the White House late Wednesday.
"Just take it, protect it, use it for yourselves," he added.
Trump has said he would consider a ceasefire only when Hormuz is "free and clear".
'Unrealistic'
Western officials have said that any action to protect seafarers using the strait could only come after a ceasefire.
"We are also convening military planners to look at how we marshal our collective defensive military capabilities, including looking at issues such as de-mining or reassurance once the conflict eases," Cooper told Thursday's meeting.
French President Emmanuel Macron said on Thursday that a military operation to liberate the Strait of Hormuz is "unrealistic".
Around a fifth of the world's oil and liquefied natural gas passes through the strait in peacetime.
The channel normally sees around 120 daily transits, according to shipping industry intelligence site Lloyd's List.
But since March 1, commodities carriers have made just 225 crossings, according to maritime intelligence firm Kpler, a 94-percent decrease on peacetime.