Lebanon's Hizbollah has trained Shia fighters from Iraq in advanced guerrilla warfare tactics, according to Mehdi army militants who have been fighting British forces in the south of the country. Members of Muqtada al-Sadr's powerful militia said they had received instruction from fellow Shias from Hizbollah, the movement that fought Israel's vaunted military machine to a bloody standstill in last year's July War.

One Iraqi militiaman, who asked to be named only as Abu Muhannad, said he had spent a month in Southern Lebanon, Hizbollah's stronghold. "I was one of the experienced fighters from the Mehdi army to go for training there," he said. "We learned how to take advantage of an armoured vehicle's weakness, and how to wait and kill the soldiers who try to escape." The 39-year-old from Suwayrah, a city 40 km south of Baghdad was one of several fighters to confirm the links between the two groups. The US has long claimed that Hizbollah, Iraq's Shias and Iran have formed a broad alliance opposed to Israel, the US and its Middle Eastern allies.

Earlier this year, the US military said it had captured a Hizbollah fighter in southern Iraq who had been involved in the abduction and murder of American soldiers. Hizbollah has a reputation of being able to carry out such complex operations, in contrast to the more amateurish Mehdi Army.

During last summer's war, Hizbollah proved itself equal to the American-supplied Israeli Defence Forces (IDF), staging well-organised, textbook ambushes on tanks belonging to the IDF. Israel invaded Lebanon expecting to crush Hizbollah, but the war ended in stalemate, surprising military observers and allowing the guerrillas to claim a victory.

Another Mehdi Army fighter, a 26-year-old who asked to be identified as Abu Nasser, said he and 100 other group members travelled to Lebanon in December 2005. "They didn't teach us anything about suicide bombings, they showed us real tactics and taught our snipers," he said. Speaking in Tufa in Iraq, Muqtada al-Sadr, the head of the Mehdi Army, admitted to "formal links" with Hizbollah.

"We have formal links with Hizbollah, we do exchange ideas and discuss the situation facing Shiites in both countries," he said. "It is natural that we would want to improve ourselves by learning from each other. We copy Hizbollah in the way they fight and their tactics, we teach each other and we are getting better through this."