TEHRAN/BEIRUT, June 20 (Xinhua) -- Iran's main military command Khatam al-Anbiya Central Headquarters announced Saturday the closure of the Strait of Hormuz, citing U.S. "breach" of the newly-signed peace memorandum of understanding (MoU) and Israel's ceasefire "violations" in southern Lebanon, Iran's semi-official Mehr news agency reported.

In this Jan. 18, 2012 photo, a tourist couple watches the mountains in south of the Strait of Hormuz as the trading dhows and ships are docked on the Persian Gulf waters near the town of Khasab, in Oman. (Photo: AP)

Meanwhile, Iranian Foreign Ministry spokesperson Esmaeil Baqaei was quoted by Mehr as saying that the Iranian negotiating team will leave Tehran for Switzerland in a few minutes.

According to a report by Iran's semi-official Fars news agency, the team will follow up on and demand the fulfillment of U.S. commitments, including forcing Israel to stop its attacks on Lebanon.

Earlier in the day, Lebanon's National News Agency reported that at least five people were killed in a series of Israeli airstrikes and drone attacks across southern Lebanon overnight and early Saturday, whereas the Israeli military said Saturday in a statement that Hezbollah launched over 50 projectiles toward its soldiers in southern Lebanon throughout the night.

The developments came despite a ceasefire agreement between Lebanon and Israel that took effect on Friday afternoon. The truce followed the signing of the MoU between the United States and Iran aiming to end conflict on all fronts, including Lebanon.