* Saif al-Islam will find pro-Gaddafi sympathies in desert
* Northern Niger, Mali unsettled by Libyan war
* Some locals vow to defy ICC arrest warrant
By Ibrahim Diallo
AGADEZ, Oct 28 (Reuters) - Muammar Gaddafi's fugitive son Saif al-Islam Gaddafi can expect a warm welcome and even help hiding among the desert communities south of Libya which were long courted by his father.
Alienated further from the West by a war which risks unsettling a fragile regional peace, some were ready to defy an International Criminal Court (ICC) arrest warrant and shelter the son of a man who for years promoted the kinship of Saharan peoples.
"We are ready to hide him wherever needed," said Mouddour Barka, a resident of Agadez in northern Niger.
"We are telling the international community to stay out of this business and our own authorities not to hand him over -- otherwise we are ready to go out onto the streets and they will have us to deal with," he added.
Earlier this week hundreds joined a communal prayer at Agadez's main mosque in memory of Gaddafi and to ask for God's blessing for his children.
A senior Libyan official said on Thursday Saif al-Islam, 39, fearing the same fate as his slain father, was trying to arrange an aircraft to fly him from a desert refuge into the custody of the ICC, the world's top war crimes court.
His location remains unclear but Libyan and other sources have suggested he is somewhere in the mountainous border region between Niger and Mali, two African countries which have signed the Rome Statute of The Hague-based court.
Niger's government in the capital Niamey has vowed to meet its ICC commitments but 750 km (400 miles) north in a region where cross-border allegiances among Tuareg nomads often outweigh national ties, the picture looks different.
"I am ready to welcome him in. For me his case is quite simply a humanitarian one," said Mohamed Anako, president of the council of Agadez region, a barren stretch of land almost the same size of France.
"Libya and Niger are brother countries and cousins. You find the same communities in Libya as you do in northern Niger -- so we will welcome him in," said Anako, who said only that he had heard "talk" of Saif al-Islam being in the area.
Aided by local Tuareg guides in a region Niger concedes is too vast for its forces to patrol effectively, Saif al-Islam could remain hidden almost indefinitely in the mountains that straddle the borders of Niger, Algeria and Mali.
Libya's southern neighbours learned to live with Gaddafi, accepting his largesse despite exasperation at his vision of a trans-Saharan people, rhetoric which prompted concerns over their territorial integrity in a region where borders are already porous.
For northern communities in both Niger and Mali, the NATO-backed Libyan war that removed Gaddafi has brought nothing but trouble, with thousands of African migrant workers and armed Tuaregs who fought for the fallen dictator turning up at their door.
This has sparked new concerns over stability in countries which have only in the past two years won respite from years of off-on Tuareg rebellions sometimes goaded on by Gaddafi.
While the security consequences for the region may take months to become clear, the build-up in recent weeks of 500 armed pro-Gaddafi fighters in the Kidal region of Mali by the Nigerien border may offer an opportunity for Saif al-Islam.
"He could be anywhere in the border region around Niger, Mali or Algeria," said a ministerial source in Mali.
"But hundreds of Libyan soldiers, all of Malian origin, are sheltering in Kidal, where they came in convoys commanded by pro-Gaddafi colonels. He would be safer among his own in Mali," the source added. (Additional reporting by Tiemoko Diallo in Bamako; writing by Mark John)