ISTANBUL, Nov 23 (Reuters) - Muslim prayer leaders in Turkey will this week use a sermon marking the end of the holy month of Ramadan to condemn terrorism and call for unity in the wake of four deadly bomb attacks in Istanbul.

Anatolian news agency said on Sunday Turkey's religious affairs directorate had revised the planned reading for the Eid al-Fitr feast in the light of the suicide bombings which killed more than 50 people over the last week.

"Terror, violence and anarchy have no connection whatsoever with Islam," the agency quoted the sermon as saying. "Our religion clearly outlaws any kind of anarchy, sedition, enmity, cruelty, torture, terror or violence."

The sermon will be read by the prayer leaders, or imams, in mosques on Tuesday, the first day of Eid al-Fitr festival. The reading said it was essential during the religious holiday to visit relatives and friends and put an end to personal differences.

"As a nation, let us show that we are living in peace and cooperation and let us make a joint stand against terrorism," the sermon said.

A statement purporting to come from a unit of Osama bin Laden's al Qaeda network said it carried out Thursday's attacks on the British consulate in Istanbul and the Turkish headquarters of the London-based HSBC Bank.

A small Turkish radical Islamist group has claimed joint responsibility with al Qaeda for those attacks and two bombs last weekend at Istanbul synagogues.