Russia blames US over Gulf tanker incident
"The situation is very concerning," said Russia's Deputy Foreign Minister Sergei Ryabkov, quoted by news agency RIA Novosti.
"The reasons for this are clear. This is Washington's deliberate, premeditated course to exacerbate tensions."
Kremlin spokesman Dmitry Peskov told journalists he was aware that "such an incident allegedly took place" but also of Tehran's denial.
"As before, we call on everyone to behave with restraint in the Persian Gulf in order not to exacerbate the situation," he said, calling for dialogue.
On Thursday, the UK said Iranian military vessels tried to "impede the passage" of an UK oil tanker but were warned off by a British warship in a dramatic escalation of tensions already present with Tehran in the Gulf.
The incident in the narrow, but busy, Strait of Hormuz occurred on Wednesday after President Donald Trump ratched up his own administration's pressure even further by warning that sanctions against the Islamic Republic would be "increased substantially" soon.
CNN initially reported that Iranian boats attempted to seize the British tanker but were driven off by a Royal Navy frigate.
The UK defence ministry said only that the Iranian boats tried to "impede" a commercial vessel called British Heritage, which is owned by British energy giant BP.
"Contrary to international law, three Iranian vessels attempted to impede the passage of a commercial vessel, British Heritage, through the Strait of Hormuz," the UK defence ministry said in a statement.
"HMS Montrose was forced to position herself between the Iranian vessels and British Heritage and issue verbal warnings to the Iranian vessels, which then turned away."
It also urged "the Iranian authorities to de-escalate the situation in the region".
Iran's Revolutionary Guards - a vast and powerful security organisation that the United States blames for staging several tanker attacks since May - denied trying to seize or impede the UK tanker.
"There has been no confrontation in the last 24 hours with any foreign vessels, including British ones," the Revolutionary Guards said in a statement.
The Revolutionary Guards also warned that the US and the UK will 'regret' seizing tanker off Gibraltar, referring to an incident earlier in the week that saw British authorities detain an Iranian ship off the coast of Gibraltar on 4 July.
Ryabkov on Thursday called the UK's actions "outrageous" saying that they violated not only international law but also European Union internal legislation.
Thursday's escalation followed reports that the US aims to form a coalition to guarantee freedom of navigation in strategic Gulf waters amid fraught relations between Washington and Tehran, a top general told media on Tuesday.
Tensions in the area - through which nearly a third of the world's oil is transported - have spiked in recent weeks, with the US blaming Iran for multiple attacks on tanker ships in the region, and Tehran shooting down an American drone.
"We're engaging now with a number of countries to see if we can put together a coalition that would ensure freedom of navigation both in the Straits of Hormuz and the Bab al-Mandab," General Joseph Dunford, chairman of the Joint Chiefs of Staff, said in a video carried by the Reuters news agency.
"I think probably over the next couple weeks we'll identify which nations have the political will to support that initiative and then we'll work directly with the militaries to identify the specific capabilities that'll support that," Dunford said.
The US would provide "maritime domain awareness and surveillance", while ships would be escorted by the nations whose flag they carry, the general said.
US Secretary of State Mike Pompeo said last month that he hopes more than 20 countries, including the UAE and Saudi Arabia, would work together on building maritime security.
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