PHOENIX: US President Barack Obama warned that victory in Afghanistan would be neither "quick" nor "easy".

"The insurgency in Afghanistan didn't just happen overnight," Obama told the Veterans of Foreign Wars service organization in the southwestern state of Arizona ahead of Afghanistan's presidential election on Thursday.

"We won't defeat it overnight. This will not be quick. This will not be easy," Obama said, explaining his strategy of intensifying the fight against the Taliban and Al-Qaeda in Afghanistan and Pakistan was now taking effect.

The president defended the war as a necessary conflict, which was "fundamental" to the defense of American people in depriving Al-Qaeda of a safe-haven to plot follow-on attacks to the September 11 strikes in 2001.

Obama noted an upsurge in "fierce" fighting in Afghanistan, but vowed to constantly adapt US tactics and ensure the troops have the tools and equipment they need to do the job. LINK