The move is the first enforcement step by a new Security Council Working Group on Children in Armed Conflict, set up late last year to prevent children 17 and under from being abducted, raped or forced into combat.

The working group's first target is the Congolese Revolutionary Movement (MRC), a militia operating in the Democratic Republic of Congo's northeastern Ituri district, where ethnic violence and clashes have killed tens of thousands of civilians.

The step was an "important landmark in the fight against impunity for those who commit grave violations against children during armed conflict," said Radhika Coomaraswamy, the U.N. special representative for children and armed conflict.

U.N. Secretary-General Kofi Annan reported to the working group in June that the MRC was forcing children into its fighting ranks.

The group's leader, Mathieu Ngudjolo, accepted a government offer of amnesty a month later in return for his men joining the national army.

Ngudjolo has boasted of having some 10,000 fighters deployed across the troubled district, but experts doubt that claim and it was unclear in any case whether they would ever show up at demobilization camps, as required by the truce.

A decision to actually impose sanctions will be up to a separate Security Council committee on Congo. U.N. sanctions on individuals typically include travel bans and asset freezes.

The vast central African country's government is seeking to integrate former rebel fighters into its security forces as it tries to put behind it a 1998-2003 civil war that pulled in armies from six neighboring countries and killed 4 million people, most of whom died from hunger and disease.

U.N. peacekeepers have been in Congo since 1999 and the mission is currently the world body's largest and most costly.

Congo held its first free multi-party elections in 40 years in late July, and a presidential runoff is due on October 29.