A coalition soldier and two Afghan nationals were killed in a roadside bomb blast in southern Afghanistan, while 25 Taliban insurgents were killed in separate clashes with Afghan and foreign forces elsewhere in the country, officials said on Saturday.

The coalition soldier and two local nationals were killed on Saturday when their vehicle was struck by a roadside bomb, US military said in a statement.

The statement did not disclose the nationality of the dead soldier. Most of the soldiers serving under command of the coalition are from the Untied States.

Meanwhile more than 25 Taliban insurgents were reported to have been killed on Saturday in separate clashes with Afghan police and NATO-led forces across the country, according to security sources.

Taliban militants, who were ousted from power in a US-led invasion in late 2001, have been fighting with Afghan and foreign forces for the past seven years.

The violence so far this year has left more than 4,000 people - mostly insurgents - dead.