MOGADISHU, (Reuters) – Ethiopia said on Tuesday it was halfway to victory against Somali Islamists and could seize their Mogadishu stronghold within days following a week of war in the Horn of Africa.

Ethiopian Prime Minister Meles Zenawi said his forces supporting Somalia’s weak interim government had killed up to 1,000 Islamist fighters. There was no independent verification of that. The Islamists also claim to have killed hundreds. He said a well-armed force of between 3,000 and 4,000 Ethiopians had “broken the back” of the Somalia Islamic Courts Council (SICC) around the government’s south-central outpost Baidoa, and that the Islamists were now in “full retreat”. “We have already completed half our mission, and as soon as we finish the second half, our troops will leave Somalia,” Meles told a news conference in the Ethiopian capital.

Ethiopia backs Somalia’s secular interim government against the Islamists who hold most of southern Somalia after seizing Mogadishu in June. Addis Ababa and Washington say the Islamists are backed by al Qaeda and by Ethiopia’s enemy, Eritrea.

Somalia’s envoy to Addis Ababa had earlier said Ethiopian soldiers had advanced to within 70 km (40 miles) of the SICC’s base in the capital, and could capture it in 24-48 hours.

The Islamists countered that any such attempt would end in disaster for the attackers. “It will be their destruction and doomsday,” SICC spokesman Abdi Kafi said. “It is a matter to time before we start striking at them from all directions.”

The Islamists claim broad popular support and say their main aim is to restore order to Somalia under sharia law after years of anarchy since the 1991 ouster of dictator Siad Barre.

Meles said his forces’ main target now were Eritrean troops he said were “hiding behind the skirts of Somali women” and foreign jihadists. He said a handful of Islamist prisoners taken on the battlefield were holding British passports.

At least two Ethiopian jets fired on Islamist forces retreating from frontlines on Tuesday shortly after the government recaptured two towns near its Baidoa outpost.

The African Union (AU) backed Ethiopia’s right to intervene in what analysts saw as a potentially significant endorsement that may embolden Meles to take Mogadishu. Diplomats say Washington has also given Ethiopia its tacit support.

AU deputy chairman Patrick Mazimhaka told the BBC that Ethiopia had given the organisation — set up to stop conflicts across Africa –“ample warning” it felt threatened by the SICC.

Diplomats fear the fighting could now draw in Eritrea on the side of the Islamists. Kenya, which is taking in a flood of Somali refugees across its north border, was working behind the scenes to broker ceasefire talks, the diplomats said.

The Islamists insisted their withdrawal and re-grouping was a tactic in what they vowed would be a long war. “We will fight to the last man until we ensure there are no more Ethiopian troops in our country,” Kafi said.

Thousands of Islamist fighters crammed into trucks mounted with anti-aircraft guns and left Mogadishu for the frontlines.

The air-strikes on Tuesday were the third day of air attacks by Ethiopian planes. Analysts say Ethiopia’s heavy arms and MiG jets had saved the government from being routed. “This is the first stage of victory … When this is all over, we will enter Mogadishu peacefully,” government spokesman Abdirahman Dinari said by telephone. He offered amnesty to Islamists who lay down their arms.

Addis Ababa fears a hardline Muslim state on its doorstep and accuses the SICC of wanting to annex Ethiopia’s ethnically Somali Ogaden region.