The security pact signed by US President Barack Obama and Afghan President Hamid Karzai, which defines America's future role in Afghanistan, doesn't rule out the possibility of drone strikes against insurgent targets in Pakistan even after the withdrawal of US troops in 2014, US Ambassador to Afghanistan Ryan Crocker has said.

The Strategic Partnership Agreement, which states that the US will not use Afghanistan as a base to launch attacks against other states, however, says that Washington and Kabul have the right of self-defense in case of threats from any country.

There is nothing in this agreement that precludes the right of self-defense for either party and if there are attacks from the territory of any state aimed at us we have the inherent right of self defense and will employ it, Crocker said while responding to a question about controversial drone strikes on Taliban and al-Qaeda targets in Pakistan, the Agence France Presse reported.

This is defensive in nature, not offensive, doesn't threaten any one, but I hope the region takes notice, he said during a briefing on the 10-year security deal.

The deal leaves room for both the nations to abandon it on a year's notice, and also allows next the US or Afghan administration to modify the terms at their own will, the AP report said.

Signed at a time when it looked increasingly unlikely that Washington and Kabul would reach a partnership agreement before the NATO conference in May, the deal demonstrates signs of hasty negotiations and loosely-built terms.

The legally binding deal demands Afghan commitment to fight corruption and protect human rights, but doesn't state any consequences if these goals aren't met.

Though the agreement affirms the need to fight the thriving business of illegal drug production and trafficking in Afghanistan, it promises nothing more than bilateral cooperation to confront the issue.

The deal promises to seek annual funding from the Congress for the training of Afghan troops, but fails to specify an estimated figure for the funding, amid concerns in Congress about the quality of these forces.

It also fails to provide a confirmation on whether the US should continue its military presence in Afghanistan, with a smaller set of troops, after the military withdrawal in 2014.

About 23,000 of the 88,000 US troops in Afghan bases are expected withdraw by the summer, while all the US and NATO combat troops would be out by the end of 2014.

In his speech addressing the US from Afghanistan, Obama sounded eager to convince Americans that his strategy is to leave the Afghan soil, winding down the war as early as strategically feasible, and focus on renewing America.

It is time to renew America, Obama said. My fellow Americans, we have travelled through more than a decade under the dark cloud of war. Yet here, in the pre-dawn darkness of Afghanistan, we can see the light of a new day on the horizon.

The Iraq war is over. The number of our troops in harm's way has been cut in half, and more will be coming home soon. We have a clear path to fulfill our mission in Afghanistan, while delivering justice to al-Qaeda.

Public opinion polls show Obama has an advantage over his Republican rival, with regard to his foreign policy and his purported eagerness to pull out troops from Iraq and Afghanistan. The deal, despite its weak terms and conditions, speaks of a mission successfully accomplished, which will be a big boost for the President on a reelection campaign trail.