Iranian President Mahmoud Ahmadinejad speaks during the opening ceremony of the International Conference on Al-Quds and Support for the Rights of Palestinian People in Tehran, Iran , April 14, 2006. -Xinhua

Iranian supreme leader Ayatollah Seyed Ali Khamenei called on Islamic countries on Friday to use all possible means to aid the Palestinian government which faces acute financial crisis.

"The Islamic nations have the duty to help you in every possible way," Khamenei told the opening ceremony of the third international conference in support for the rights of the Palestinian people in Tehran.

Attacking the United States and European Union for their pro-Israel position to isolate and starve the new Hamas-led government, Khamenei said, "the Islamic world cannot remain indifferent and silent to tyranny."

The three-day conference is being held on the initiative of Khamenei.

Iran's President Mahmoud Ahmadinejad, Majlis (parliament) Speaker Gholam-Ali Haddad-Adel, Judiciary Chief Mahmoud Hashemi Shahroudi and other senior officials attended the opening ceremony. Iran does not recognize Israel, and hardline President Mahmoud Ahmadinejad has called for the Jewish state to be "wiped off the map".

Some 600 delegates from 50 countries, including 26 parliament speakers, as well as the representatives from militant groups Hamas, Islamic Jihad and Hezbollah also attended the gathering. Earlier Friday, Palestinian Prime Minister Ismail Haneya vowed not to back down in face of aid cuts.

Hamas has refused to renounce violence, recognize Israel's right to exist and accept previous deals signed with the Jewish state, the conditions set by Israel and its Western allies for dealing with Hamas following its election victory in January. Meanwhile, Palestinian Foreign Minister Mahmoud al-Zahar kicked off a trip to Arab nations on Friday in a bid to secure political support and much needed aid to the cash-strapped Hamas government. The two-week tour will bring him to Egypt, Jordan, Syria, Saudi Arabia, Kuwait and Bahrain.