The United States has lodged a formal diplomatic protest with Iran over a weekend incident in which Iranian speedboats harassed US warships in the Persian Gulf's Hormuz Strait, the State Department said Thursday. The protest, which reiterates earlier US complaints about the "provocative" action, was sent to the Iranian Foreign Ministry through the Swiss Embassy in Tehran, which looks after US interests in Iran, deputy spokesman Tom Casey told reporters. He could not say whether the Iranians had received and acknowledged receipt of the protest "We have ... prepared and given to the Swiss a diplomatic note formally protesting this incident," Casey said. "It reiterates the points that we have made publicly in the last few days." Casey said: "We certainly don't want to see the Iranians taking any kind of provocative actions or provocative steps against our ships or against any ships that are transiting what is a primary international waterway," Casey said. He dismissed Iranian claims that nothing was unusual about Sunday's incident in the Strait of Hormuz as well as a videotape aired by Iranian television on Thursday that appeared to have been an attempt to show that there was not a confrontation between vessels of the two countries.