The US Justice Department on Tuesday accused agents of the Iranian government of being involved in a plot to assassinate Adel Al-Jubeir, the Saudi ambassador to the United States, with help from a purported member of a Mexican drug cartel. The Saudi Embassy here has termed the plot “despicable”, saying it violated “the principles of humanity.” Attorney General Eric Holder said the US would hold Iran accountable. Secretary of State Hillary Rodham Clinton said the US is preparing for new sanctions against the Republic. According to the US, two people, including a member of Iran's special operations unit known as the Quds Force, were charged in New York federal court. Holder said the alleged bomb plot was a flagrant violation of US and international law. “We will not let other countries use our soil as their battleground,” Preet Bharara, the US attorney in Manhattan, said at a news conference in Washington with Holder and FBI Director Robert Mueller. Manssor Arbabsiar, a 56-year-old US citizen who also holds an Iranian passport, was charged along with Gholam Shakuri, whom authorities said was a Quds Force member. FBI Director Robert Mueller says many lives could have been lost in the plot to kill the ambassador with bombs in the US. Holder said the US government would be taking unspecified action against the Iranian government as early as Tuesday. Asked whether the plot was blessed by the top echelons of the Iranian government, Holder said the Justice Department was not making that accusation. Arbabsiar, allegedly, unknowingly hired an informant from the Drug Enforcement Administration to carry out the plot, prosecutors said. Posing as a member of a Mexican drug cartel, the informant met with Arbabsiar several times in Mexico, authorities said. The price tag was $1.5 million and Arabsiar made a $100,000 down payment. Bharara said no explosives were actually placed, and no one was in any danger. Shakuri remains at large. Arbabsiar was arrested Sept. 29 at New York's John F. Kennedy International Airport. He was scheduled to appear in federal court Tuesday. Prosecutors said he faces up to life in prison if convicted. Prosecutors said Arbabsiar has confessed to his participation in the murder plot. On Tuesday, Abdullah Alshamri, a Saudi official in Riyadh, predicted that the disclosure would send Iranian-Saudi relations to “their lowest point yet,” the New York Times reported. “We're expecting from our government a serious and tough reaction, to give a message to the Iranians that enough is enough,” he said in a telephone interview. “If we keep our diplomatic ties with the Iranians, they will think we are weak, and they will keep trying to attack us.”