The leader of Lebanon's mainly Shia movement Hezbollah says US President Barack Obama's promise to engage with Muslims has proved to be false, BBC reported.
Hassan Nasrallah said the US had shown its commitment to Israel by sending more military aid and backtracking on demands to stop West Bank settlements.
He said the Arab world could not depend on the US to solve its problems because the US was causing them.
In June, Mr Obama called for a "new beginning" between the US and Muslims.
Correspondents say that Mr Nasrallah's remarks were his strongest criticism yet of the US president.
"A few months ago, when Barack Obama was elected as US president and a new American administration saw light, many had high hopes and believed that major changes will happen in favour of the Arab and Islamic world," said Mr Nasrallah, quoted by Hezbollah's al-Manar TV.
"However, the truth was quickly revealed and all these illusions quickly failed. The result was obviously a full US commitment to Israel's interest and security, disregarding the dignity and feelings of the Arab and Muslim people and governments."
He added: "We tell all those who asked us to give the Americans some time... it turned out that presenting a black president from the third world was a trick that ended faster than we expected."
Mr Nasrallah was speaking on Hezbollah's Martyrs' Day.
Earlier this week, the head of Israel's military said that Hezbollah now has rockets capable of reaching Israel's largest cities.
Maj Gen Gabi Ashkenazi's warning came days after Israel's navy seized a ship it said was carrying hundreds of tonnes of weapons destined for Hezbollah.
Israel and Hezbollah fought a war in 2006 during which more than 1,200 Lebanese, mostly civilians, were killed. Some 160 Israelis, most of whom were soldiers, also died.