By Souleymane Ag Anara
KIDAL (Reuters) - A few stale and mouldy loaves are all that is left in the main bakery of Mali's northern desert town of Kidal.
The owners abandoned it when flour prices doubled after armed fighters from a mostly Tuareg group blockaded the town, which sits at a critical smuggling crossroads, last month.
The blockade is part of a bitter feud between rival Tuareg clans which is undermining attempts to implement a 2015 peace deal and stabilise northern Mali and, by extension, the Sahel.
Tens of millions of dollars in Western aid to address the root causes of cyclical Tuareg uprisings in the north are on hold until tensions between the armed groups, symbolised by the Kidal blockade, have eased.
The absence of a legitimate army in the north has left a gap allowing bands of Islamist militants, who were scattered but not defeated by a 2013 French military operation, to become increasingly brazen.
Addressing the grievances of secular Tuareg armed groups, thought to comprise thousands of fighters, is seen as an essential step towards countering roaming jihadists, who are tied to them both in kinship and business, and have always exploited their grievances.
"There's no chance of taking the fight to Islamic terrorists if the Tuareg conflict is not resolved first," said Sean Smith, West Africa Political Risk Analyst at Verisk Maplecroft. "We've seen the limits of foreign intervention and Tuaregs need to be part of the security solution."
Already, Islamic militants are launching more sophisticated attacks on U.N. peacekeeping force MINUSMA and are blamed for multiple strikes in neighbouring countries, such as a prison attack in Niger on Monday. [L8N1CN1MA]
Clashes between fighters from the two heavily-armed sides -- the pro-government Platform coalition, led by the GATIA militia and the separatist Coordination of Azawad Movements (CMA) -- have broken out repeatedly since July, killing 39, the United Nations says.
"The first violations of the ceasefire... in Kidal have endangered the peace process, pushing back the appointment of interim administrations and the launch of mixed security patrols," U.N. peacekeeping chief Herve Ladsous said this month, referring to patrols meant to incorporate Tuaregs as well as the Malian army.
Mali's semi-nomadic Tuareg population of fewer than 1 million have survived on the edges of the world's largest desert by dominating trans-Saharan smuggling routes for smuggling goods from gold to spices.
Today, transporting cocaine and migrants through Mali to Niger and Algeria is more lucrative and attempts to dominate routes leading there from Kidal have been a major source of tension between the two Tuareg-led armed groups.
Security sources say GATIA, led by Malian army general El Hadj Ag Gamou, is also driven by historical grievances, since members are drawn mostly from the Imghad clan which for decades were "vassals" to the noble Ifoghas leading the CMA.
Kidal, which has been beyond the authority of the southern government since the last Tuareg rebellion in 2012, was due to be jointly administered by the two sides.
Instead, CMA seized back the town in August. On the dusty streets, their turbaned fighters roll past abandoned shops in heavily-armed pick up trucks, decorated with the colourful flags of their longed-for state known as Azawad.
Residents say GATIA are turning away food and humanitarian supplies at make-shift checkpoints outside town in what one security source called an attempt to "asphyxiate" Kidal.
Food, in short supply in the arid region, cannot be flown in because the airport is closed. "They are trying to crush Kidal," said Ilad Ag Mohamed, a CMA spokesman.
Haballa Ag Hamzata, deputy Secretary General of GATIA, confirmed the group was controlling most roads into town.
"We said that we would no longer accept humanitarian aid into Kidal if the Platform is not associated with distributing it," he told Reuters.
For now, U.N. and French troops are there to deter any GATIA attempt to take back Kidal. They patrol the eerily quiet streets daily in armoured vehicles, past worn-out posters promoting lapsed aid projects.
But the death of CMA commander Cheikh Ag Aoussa last week in an alleged assassination attempt near the MINUSMA camp shows their vulnerability even within their stronghold.
Tit-for-tat killings are common in areas beyond the reach of patrols and the United Nations says it is investigating allegations of serious human rights violations.
Takdiss Walet, a resident of Intachdayte, 80 kilometres away, told Reuters she fled to Kidal last month after GATIA fighters killed two male family members.
Western diplomats whose governments have pledged billions of dollars for Mali have reproached Bamako, which is supposed to be implementing the peace deal and restoring state authority in the north, for ties with the group.
A spokesman for the government, which has always denied links to the group, was not available for comment.
Impatience with CMA is also growing, with evidence of links between them and jihadists becoming harder for Western observers to ignore. In a stark example, the death of Ag Aoussa was eulogised by al Qaeda in the Islamic Maghreb on social media.
CMA and Platform clashed last year and then ended their feud in October at Anefis. However, analysts say trust levels are even lower now.
"As long as North Mali is not functioning, then Islamist groups can operate freely across the whole region," said Smith.
(Additional reporting by Tiemoko Diallo in Bamako; Writing and additional reporting by Emma Farge in Dakar; Editing by Tim Cocks and Anna Willard)