TEHRAN — Iran has strongly denied any involvement in the attack on an Israeli-managed tanker off the coast of Oman last week in which two crew members — a Briton and a Romanian — were killed. The Iranian denial comes after the United States, Britain and Israel blamed Iran for the deadly attack. On Sunday, US Secretary of State Antony Blinken issued a statement condemning the attack. "We join our partners and allies in our strong condemnation of the attack against the Mercer Street, a commercial ship that was peacefully transiting through the north Arabian Sea in international waters." "Upon review of the available information, we are confident that Iran conducted this attack, which killed two innocent people, using one-way explosive UAVs, a lethal capability it is increasingly employing throughout the region," Blinked added in his statement. The US secretary of state said that there is no justification for this attack, which follows a pattern of attacks and other belligerent behavior. "These actions threaten freedom of navigation through this crucial waterway, international shipping and commerce, and the lives of those on the vessels involved." Blinken added: "We are working with our partners to consider our next steps and consulting with governments inside the region and beyond on an appropriate response, which will be forthcoming." He offered condolences to the families of the victims. British Foreign Secretary Dominic Raab also condemned the attack in a statement on Sunday. "The UK condemns the unlawful and callous attack committed on a merchant vessel off the coast of Oman, which killed a British and a Romanian national. Our thoughts are with the friends and family of those killed in the incident," Raab said. "We believe this attack was deliberate, targeted, and a clear violation of international law by Iran. UK assessments have concluded that it is highly likely that Iran attacked the MV Mercer Street in international waters off Oman on July 29 using one or more unmanned aerial vehicles (UAVs)." The UK foreign secretary added: "Iran must end such attacks, and vessels must be allowed to navigate freely in accordance with international law." Raab said that the UK is working with our international partners on a concerted response to this unacceptable attack. On Monday, the UK foreign ministry summoned the Iranian Ambassador to the UK on Monday. This was in response to the unlawful attack on a merchant's vessel off the coast of Oman on July 29, in which a British national and Romanian national were killed. A Foreign, Commonwealth & Development Office spokesperson said: "The Iranian Ambassador to the UK, Mohsen Baharvand, was summoned today to the Foreign, Commonwealth & Development Office by the Minister for the Middle East, James Cleverly, in response to the unlawful attack committed on MV Mercer Street on July 29. Minister Cleverly reiterated that Iran must immediately cease actions that risk international peace and security, and reinforced that vessels must be allowed to navigate freely in accordance with international law.