INTERVIEW-U.S. will urge Ethiopia to stay out of Somalia

* Djibouti to help African peacekeeping force AMISOM

*Washington undecided on tougher force mandate

By David Clarke

NAIROBI, July 4 (Reuters) - The United States will encourage Ethiopia not to return to Somalia as it would be against the interests of both Horn of African nations, Assistant Secretary of State for African Affairs Johnnie Carson said on Saturday.

Ethiopia invaded Somalia in late 2006 to topple an Islamist movement in the capital Mogadishu. The intervention sparked an Islamist insurgency which is still raging despite the fact Ethiopian troops pulled out in January.

"The Ethiopian government continues to look very closely at developments in Somalia," Carson told Reuters in Kenya ahead of a visit to Ethiopia on Monday.

"Given the long-standing enmity between Somalis and Ethiopians I will encourage the Ethiopians not to re-engage in Somalia. It is not their interest to so and their efforts might in fact prove counterproductive to the government," he said in an interview.

Neighbours and Western governments fear that if the Somali administration is overthrown, the lawless nation will become a safe haven for al Qaeda to train militants to destabilise the region and attack developed nations.

Residents in several regions of Somalia have reported seeing Ethiopian soldiers in the past two months. Addis Ababa initially denied this but later acknowledged it had made "reconnaissance" missions. It still insists no combat troops are in Somalia.

"Ethiopia has a right to defend its borders, should do so vigorously if individuals cross into their territory, and their efforts should be directed at defence of their territory and not necessarily involvement inside of Somalia," Carson said.



NO DECISION ON TOUGHER MANDATE

Carson held talks with senior officials from all Horn of Africa countries, including the Eritrean foreign minister, during an African Union summit in Libya this week.

Washington has accused Eritrea of supporting the hardline al Shabaab insurgents who are fighting to oust Somali President Sheikh Sharif Ahmed. It says Eritrea has aided the movement of weapons and foreign fighters into Somalia.

Carson said Eritrea strongly denied the accusations.

The rebels, who have links to al Qaeda and want to impose their own harsh version of sharia law throughout the country, control much of southern Somalia and parts of the capital Mogadishu close to the president's palace.

A 4,300-strong African Union peacekeeping force (AMISOM) from Uganda and Burundi is protecting key sites in Mogadishu but appeals for more troops and a stronger mandate allowing them to go on the offensive have yet to bear fruit.

Carson said a battalion of soldiers from Burundi, about 800 troops, was ready to deploy as soon as an airlift is provided and that Djibouti had pledged to help with military force.

"They are a small country with a small military but they have indicated that they believe the situation is serious enough to warrant their support," Carson told Reuters.

"They believe that it is important to support Sheikh Sharif and to prevent his government from falling and they are prepared to provide more support than they have in the past, including manpower," he said.

Carson said Washington had yet to decide whether the AMISOM mandate should be beefed up. There had been hopes African leaders would agree to this in Libya but wording to that effect in a draft resolution was dropped.

"We will study it closely in Washington and make a determination as to whether it is in our interests to encourage an expanded mandate as this goes forward," he said.

Washington helps fund the AMISOM force and has sent weapons to the Somali government to support its fight against the rebels. Carson told reporters it would send more.

"The United States will continue to look for ways to provide support," he said. "This will include military support in terms of arms and munitions and material resources, but not manpower."

(Editing by Sonya Hepinstall)