UNITED NATIONS: The UN Security Council voted unanimously Thursday to extend the mandate of the Nato-led force in Afghanistan for the last time before it hands over total responsibility for security to Afghan forces at the end of 2014.

The resolution adopted by the council said the situation in Afghanistan ''still constitutes a threat to international peace and security.''

It expressed serious concern about security in the country, pointing to ongoing violence and terrorist activities by the Taliban, al Qaeda, and other illegal and extremist groups as well as by criminals and those involved in the illegal drug trade.

The Taliban have escalated attacks in recent months as they try to take advantage of the withdrawal of foreign troops.

In June, Afghan forces took the lead for security nationwide, leaving the Nato-led International Assistance Force known as Isaf entirely in a supporting, backseat role.

Isaf has dropped dramatically in strength as it prepares to leave, down from 130,000 troops two years to just over 87,200 troops on Aug 1, including 60,000 Americans.

The Security Council extended Isaf's mandate until Dec 31, 2014, the final day for transferring full security responsibility to the Afghan government.

Its action followed an outburst Monday from Afghan President Hamid Karzai who alleged that the US and Nato inflicted suffering on the Afghan people and repeatedly violated its sovereignty.

Despite his critical remarks, the Obama administration is still optimistic that a US-Afghan agreement over the future role of American troops in the country can be finalized in the next few weeks.

Karzai made the comments on the 12th anniversary of the start of the American campaign in Afghanistan against al-Qaida that ousted its Taliban allies from power.

The invasion was in response to the Sept 11 attacks on the United States, which claimed nearly 3,000 lives.

The Security Council welcomed a 2010 agreement between Nato and Afghanistan to provide practical support to improve Afghanistan's ''capacity and capability to tackle continued threats to its security, stability and integrity.''

It encouraged Isaf and other partners to accelerate the training and mentoring of the Afghan National Security Forces, now numbering more than 350,000 men and women.

The council said the goal is to have an Afghan force that is ''self-sufficient, sustainable, accountable and ethnically balanced,'' and is able to provide security and ensure the rule of law throughout the country.