Ethiopia resisted international pressure for mediation in a war in the country's north on Monday as its air force bombed sites in and around the Tigrayan capital Mekelle, according to diplomatic and military sources.Hundreds have died, 25,000 refugees have fled to Sudan and there have been reports of atrocities since Prime Minister Abiy Ahmed ordered air strikes and a ground offensive on Nov. 4 against Tigray's local rulers for defying his authority. But Africa's youngest leader, who won a Nobel Peace Prize last year, has so far resisted pressure for talks to end a conflict that has spilled into neighboring Eritrea and threatened to destabilize the wider Horn of Africa."We are saying 'Give us time'. It's not going to take until eternity ... it will be short-lived operation," Redwan Hussein, spokesman for the government's Tigray crisis task force, told reporters."We have never asked Uganda or any other country to mediate," Redwan added, after Uganda's President Yoweri Museveni met Ethiopia's foreign minister and appealed for negotiations.Ethiopia's air force dropped bombs in and around Mekelle on Monday, four diplomatic and military sources told Reuters.The sources had no word on casualties or damage. There was no immediate information from the Ethiopian government, but Tigrayan local authorities and TV said the bombing happened mid-morning.The Tigray flare-up could jeopardize the recent opening up of Ethiopia's economy, stir ethnic bloodshed elsewhere around Africa's second most populous nation, and tarnish the reputation of Abiy, 44, who won his Nobel for pursuing peace with Eritrea.The Tigray People's Liberation Front (TPLF), which governs the region of 5 million people, has accused Eritrea of sending tanks and soldiers over the border against it.Eritrea denies that.Tigray forces fired rockets into Eritrea at the weekend.Ethiopia's task force said federal troops had "liberated" the town of Alamata from the TPLF in southern Tigray after saying last week they had seized the west.With communications mainly down and media barred, Reuters could not independently verify assertions made by all sides.'INFLICTING SUFFERING'There was no immediate comment from Tigray's leaders about Alamata, about 120 km (75 miles) from Mekelle.TPLF leader Debretsion Gebremichael urged the United Nations and African Union to condemn Ethiopia's federal troops, accusing them of using high-tech weaponry including drones in attacks he said destroyed a dam and a sugar factory."Abiy Ahmed is waging this war on the people of Tigray and is responsible for the purposeful infliction of human suffering," he said.The government has denied targeting the dam or civilian locations, but has not commented on the sugar factory.Tigray leaders accuse Abiy, from the largest Oromo ethnic group, of persecuting them and purging them from government and security forces over the last two years. He says they rose up against him by attacking a military base.Amnesty International has denounced the killing of scores and possibly hundreds of civilian labourers in a massacre that both sides have blamed on each other.Museveni tweeted that he met Demeke Mekonnen, Ethiopia's foreign minister and deputy prime minister, in Uganda."There should be negotiations and the conflict stopped, lest it leads to unnecessary loss of lives and cripples the economy," he said in a tweet later deleted.REGIONAL EXHORTATIONSDemeke went on to Kenya afterwards."Everybody is encouraging talks, it's very urgent," said Mahboub Maalim, a Kenyan diplomat who heads the Nairobi-based regional think-tank Sahan. "We should focus on a ceasefire."Kenya and Djibouti urged a peaceful resolution and the opening of humanitarian corridors, while Nigeria's former president Olusegun Obasanjo went to Ethiopia.European nations were also weighing in, diplomats said, with Norway planning to send a special envoy.One diplomat said Ethiopia's army was reporting it had retaken 60% of Tigray and was planning a multi-pronged offensive on Mekelle, aiming to reach it in three days.The Ethiopian National Defence Force has around 140,000 personnel and plenty of experience from fighting Somali militants, rebels in border regions, and Eritrea.But many senior officers were Tigrayan, much of its most powerful weaponry is there and the TPLF has seized the powerful Northern Command's headquarters in Mekelle.The TPLF itself has a formidable history, spearheading the rebel march to Addis Ababa that ousted a Marxist dictatorship in 1991 and bearing the brunt of the 1998-2000 war with Eritrea that killed hundreds of thousands.Eritrea's President Isaias Afwerki – a long-time foe of the Tigrayan leaders - controls an army that the United States' CIA puts at 200,000 personnel.