KABUL - Reclusive Afghan Taliban leader Mullah Mohammad Omar has urged insurgent fighters, who he said had successfully infiltrated the security forces, to avoid civilian deaths after a swathe of suicide bombings this week killed 63 people.

In a message to the Afghan people ahead of the Eid al-Fitr festival ending the holy Ramadan fasting month, the one-eyed leader said insurgents should "employ tactics that do not cause harm to life and property of the common countrymen".

"The instructions given to you for the protection of civilian losses are, on you, a religious obligation to observe," Mullah Omar said in a seven-page statement released late on Thursday and translated into five languages.

"Any violation readily incurs loss in this world and in the world to come.

Therefore, I urge you emphatically to be careful about the civilian losses and take this on yourselves as an explicit responsibility."

Amid mounting anger among Afghans over civilian deaths caused by both the insurgency and NATO, the statement is probably aimed at presenting a more moderate face for the Taliban as efforts continue to re-start peace talks which could foster a power-sharing deal for the insurgency.

A recent UN report said the Taliban were responsible for 80 percent of civilian casualties.