By Barry Malone

ADDIS ABABA, Sept 6 (Reuters) - An Ethiopian rebel group on Monday warned foreign oil and gas firms to stay out of the country and rejected government claims that the disputed Ogaden region was now safe for exploration companies.

The Ogaden National Liberation Front (ONLF), which is fighting for the mainly ethnic-Somali Ogaden's independence, was responding to the country's mines and energy minister, Alemayehu Tegenu, who last week said the area was secure.

"(Alemayehu's) claim that his regime's military is in control of Ogaden is wishful thinking and is designed to give a false sense of security to oil firms who seek to exploit the oil resources of Ogaden," an ONLF statement said.

"The renewal of security assurances for Ogaden by the regime to oil firms is therefore a dangerous step as the policy of the ONLF in this regard remains unchanged."

Alemayehu said the government was in negotiations to give three more foreign mineral firms licenses to explore for oil and gas in the Horn of Africa country. He did not say whether the sites were in the Ogaden.

Ethiopia says the Ogaden basin may contain gas reserves of 4 trillion cubic feet and points to oil-producing neighbours such as Sudan and Yemen as evidence there could be major oil deposits.

Apart from a small discovery of natural gas, no significant oil or gas finds have been made. Twelve foreign firms, including Vancouver-based Africa Oil Corporation (AOI.V) and Malaysia's Petronas, are exploring Ethiopia's deserts.

"WAR CRIMES"

"Oil firms should know that by partnering with this regime in Ogaden they are effectively turning a blind eye (to) war crimes often perpetrated in their name," the ONLF statement said.

Ethiopian forces launched an assault on the ONLF after a 2007 attack on an oil exploration field owned by a subsidiary of China's Sinopec Corp (0386.HK)(600028.SS), Asia's biggest refiner, left 74 people dead.

Last July, a British geologist was shot dead in the Ogaden while working for IMC Geophysics International, subcontracted to Petronas. The ONLF denied involvement and the government said "bandits" were responsible.

Both sides accuse the other's forces of killing and raping civilians.

The ONLF routinely claims victories over the Ethiopian army. The Ethiopian government has admitted to some small skirmishes with the rebels in the past year but Prime Minister Meles Zenawi said the ONLF had been crushed.

The tit-for-tat accusations are hard to verify. Journalists and aid groups cannot move freely off the region's main roads without government escorts.

Analysts say the rebels are incapable of ousting the government but can hamper development and weaken security forces in the Ogaden with hit-and-run attacks. (Editing by Richard Lough)

Reuters