Kabul, Afghanistan (CNN) — Secretive Taliban leader Mullah Omar signaled support for Afghan peace talks in a message to supporters Wednesday (July 15).

"Concurrently with armed jihad, political endeavors, and peaceful pathways for achieving these sacred goals is a legitimate Islamic principle and an integral part of Prophetic politics," he said in a message released on the eve of Eid celebrations to mark the end of Ramadan.

The Taliban leader said he had ordered the formation of a "Political Office" that was "entrusted with the responsibility of monitoring and conducting all political activities."

"The objective behind our political endeavors as well as contacts and interactions with countries of the world and our own Afghans is to bring an end to the occupation and to establish an independent Islamic system in our country," he said, after explaining at length why negotiating with "infidels" is permitted by the Quran and actions of the Prophet Mohammed.

His message comes a week after the Afghan government held face-to-face talks with Taliban representatives for the first time in an attempt to work toward a peace process.

Mujahedeen told to stay united

Mullah Omar also sent an apparent warning to ISIS, the Sunni extremist group that has seized a swath of territory across Syria and Iraq, not to create a new front in Afghanistan.

"Since maintaining the unity of jihadi front in our country is a religious obligation, we have therefore directed all our mujahedeen to preserve their unity and forcefully prevent all those elements who attempt to create differences, damage this jihadi front or try to disperse the mujahedeen," he said.

His words come after ISIS published a long interview in its English-language propaganda magazine, Dabiq, in which a Muslim scholar argued that jihadi forces should back the self-declared caliphate of leader Abu Bakr al-Baghdadi over the "regional" leader Mullah Omar.

Insurgency rages

The Afghan government described last week's talks, hosted by Pakistan, as "the start of the first ever official peace talks" between the two sides.

Afghan President Ashraf Ghani had been seeking dialogue with the Taliban with the encouragement of the United States.

But finding a peaceful resolution to the country's lengthy conflict will be challenging, to say the least.

As U.S. and other NATO troops are drawing down their numbers in Afghanistan, the Taliban insurgency continues to rage across wide areas of the country. The militants attempted a brazen attack on the national parliament last month.

The U.S. combat mission in Afghanistan ended last year, leaving the Afghan military to lead the fight against the Taliban. The thousands of NATO troops that remain in Afghanistan are there in a training and support role.

CNN's Jethro Mullen and Sophia Saifi contributed to this report.

This story was first published on CNN.com, "Taliban leader Mullah Omar backs Afghan peace talks."