US President Donald Trump said Thursday he would hold Iran responsible for attacks on shipping by Yemen's Houthis and threatened both with "major military punishment." Trump's warning came after the Tehran-backed Houthis launched missile and drone strikes on oil tankers in the Red Sea to enforce what they said was a blockade on Saudi Arabia, AFP reported. "The US will hold Iran responsible, in that the Houthis are a Surrogate and/or Proxy of Iran, and major military punishment will be inflicted upon Iran and, of course, the Houthis themselves" should they launch further attacks, Trump said on his Truth Social network. Trump said he was "very disappointed" by the Houthis as they had "until now, acted very professionally and smart" following US attacks on the group last year, and during the Iran war that the United States and Israel launched in February. The Houthis hit a Saudi ship in the Red Sea on Wednesday, bringing the Middle East war to a new front and sending oil prices surging. Earlier this week, the Houthis said they had struck two Saudi oil tankers after declaring a blockade of Saudi ports.