By Andrew Heavens

KHARTOUM (Reuters) - Sudan wants European peacekeepers to pay $40,000 compensation after four nomads were killed as they tried to retrieve the body of a French soldier near the border with Chad, a foreign ministry official said.

The French special forces sergeant was shot after he accidentally crossed into Sudan from Chad last week and came across a Sudanese army checkpoint.

Sudan's army said four nomads later found the soldier's body and were killed when one of his hand grenades exploded as they tried to load him on to a camel.

Sudan's foreign ministry on Monday said officials had requested compensation from a European Union delegation which flew to Khartoum to collect the sergeant's body on Friday.

The move is set to enrage public opinion in France which has already made an official complaint to Sudan over the shooting.

The man's death was the first casualty for the 3,700-strong EUFOR force that is still deploying in Chad with a United Nations mandate to provide security for more than 400,000 people in eastern Chad. More than half of the force will be provided by France.

"It is customary here in Sudan that whenever a person is killed unintentionally, the next of kin will be paid compensation," said Sudanese foreign ministry spokesman Ali al-Sadig.

"This was not done on an official basis. But an informal request was made to EUFOR (the European Union security force in Chad)."

"It is customary law that you pay an amount of about $10,000 per person," he added. The European officials, he said, had promised to pass the request on to their headquarters.

Al-Sadig said France would not be entitled to use the same custom to demand compensation for the dead French soldier as he had been killed in an exchange of fire.

On Friday, French President Nicolas Sarkozy condemned what he called the "deliberate and disproportionate" use of force by Sudan in the killing of the soldier.

France's defence ministry said the French soldier and a colleague had identified themselves after encountering the checkpoint but had immediately come under fire. The second soldier was wounded but managed to return to EU forces.

Sudan said a military jeep that entered from Chad carrying six French soldiers opened fire on a Sudanese army position.

French and EU officials previously said they regretted the border incursion.

Analysts say Sudan has long resisted the presence of a foreign military presence so close to its western border with Chad. Khartoum has already refused to accept non-African troops in the joint U.N./African Union peacekeeping force that is also currently deploying in its war-torn Darfur region.