Somali President Sheik Sharif Sheik Ahmed speaks to journalists, in Mogadishu (File)

Somalia's president has declared a state of emergency as his government tries to fight off an offensive by militant Islamist groups.

President Sharif Sheikh Sharif Ahmed spoke to reporters in the capital Mogadishu Monday, following calls from his aides for intervention by foreign troops.

Insurgent groups launched an offensive in Mogadishu May 7, sparking clashes that have killed some 300 people and displaced at least 120,000.

Earlier, the African Union voiced support for the Somali government, saying it "has the right" to seek help from AU member countries and the international community.

In Kenya Monday, Prime Minister Raila Odinga also said Somalia needs military assistance, though he stopped short of saying Kenya will send troops across the border.

Mr. Odinga spoke at a joint news conference with Somali Prime Minister Omar Abdirashid Ali Sharmake.

Ethiopia helped prop up the fragile Somali government for more than two years before withdrawing its troops in January.  

Witnesses in central Somalia said Ethiopian forces re-entered the country last month and have positioned themselves in at least two border towns.  Ethiopia denied those reports, though it admitted to conducting cross-border "reconnaissance missions."

Al-Shebab fighter guards a crowd in Mogadishu during a court session run by the Islmaist group, 22 Jun 2009

The main insurgent groups, al-Shabab and Hizbul Islam, have vowed to fight any foreign troops that enter the country.

The groups have clashed at times with an African Union peacekeeping force of about 4,000 stationed in Mogadishu.

The insurgents control much of southern Somalia after an insurgency that began in 2007.  

The government says the insurgents are being helped by hundreds of foreign jihadists, or Islamic fighters.

The insurgents say they are fighting to topple the Somali government and install an Islamic state.  President Sharif, a moderate Islamist, has introduced Sharia (Islamic) law in Somalia, but the hardline groups reject the move as insufficient.

Some information for this report was provided by AFP.