An Islamist leader who wants to see Mali adopt sharia law vowed Tuesday to support regional mediation efforts to resolve the ongoing political crisis in the ruptured west African nation.

Iyad Ag Ghaly, who heads the Ansar Dine Islamist group that holds the northern city of Kidal and other towns, met with Burkina Faso's Foreign Minister Djibrill Bassole, who is leading the search for a peaceful solution to the 20-week-old emergency that has seen Islamists seize Mali's north.

"We are pleased. We support and accept the mediation of (Burkinabe) President (Blaise) Compaore," Iyad Ag Ghaly told reporters.

"God willing, we will go down this road together. God will help everybody find what they're after," he said, clad in a blue robe and white turban.

Iyad Ag Ghaly is a renowned former leader of Mali's Tuareg separatist rebellion who resurfaced earlier this year as the head of the previously unknown Islamist group Ansar Dine (Defenders of Faith, in Arabic).

Bassole, the highest-ranking diplomat to visit northern Mali since Islamist fighters seized the region in late March, made the trip to assess the chances of a peaceful solution to the crisis.

The Burkinabe foreign minister, whose boss Compaore was appointed by ECOWAS as the lead mediator in Mali, also visited the desert city of Gao, which is controlled by Al-Qaeda offshoot the Movement for Oneness and Jihad in West Africa (MUJAO).

The unprecedented trip, under the aegis of the Economic Community of West African States (ECOWAS), marks an attempt by the regional bloc to rekindle diplomatic efforts and avert a military intervention.

Bassole started the trip with a visit to Gao's main hospital, where chief doctor Moulate Guiteye told him: "Thanks to the assistance of aid groups, we have enough medicine."

Surrounded by veiled nurses, the doctor explained however that the hospital had been forced to enlist residents to help because several staff members had fled following the Islamist takeover.

Cut off from Mali's southern region, about half the town's population have fled, leaving some 35,000 residents in the sandy city of ancient mud tombs and low-slung buildings located about 1,200 kilometres (750 miles) north-east of the capital Bamako.

Bassole, who served as a chief United Nations-African Union mediator in Sudan's Darfur crisis, also spoke with local leaders but did not talk to anyone from MUJAO.

He said he was "bringing a message of peace".

"Despite the gravity of the situation" and dramatic events in the region, "there must be room for dialogue," he said, adding he hoped to see a complete end to hostilities soon.

400,000 displaced

The Islamists, who piggy-backed on and then snuffed out a military offensive by Tuareg separatists to seize control of northern Mali -- an area larger than France or Texas -- are enforcing Islamic law, or sharia, with varying degrees of strictness.

In the most gruesome such incident since Mali's de-facto partition, an unmarried couple was publicly stoned to death by Islamist fighters in the small town of Aguelhok last month.

Gao, a key hub in northern Mali, has shown some resistance to MUJAO's attempts to implement sharia, most recently when a crowd prevented the militiamen from cutting off the hand of an alleged thief.

The conflict has displaced more than 400,000 people in a region already wracked by drought. Half of them have fled across Mali's borders to rudimentary camps in Burkina Faso, Niger and Mauritania, some of the world's poorest nations.

ECOWAS says it is ready to send 3,300 troops into Mali, but is awaiting a formal request from a yet-to-be-formed unity government in Bamako and a mandate from the UN Security Council.

France has called an African military intervention "desirable and inevitable", but Defence Minister Jean-Yves Le Drian said the former colonial power would not take the lead.

Also Tuesday, three men pleaded not guilty in a Bamako court for their alleged role in organising a May protest during which interim president Dioncounda Traore was brutally attacked by a mob of angry protesters who stormed his office.

Traore, 70, spent two months recovering in Paris before returning to Mali on July 27.