Singh also lauded Karzai's personal leadership and the courage, resolve and determination of the people of Afghanistan, who had defied terrorism and violence and voted for a democratic and prosperous future of their country, a PMO release said.
"President Karzai expressed his gratitude to the Prime Minister and said that Afghanistan was grateful for the support and assistance that had consistently been extended to it by India," the release said.
Karzai said the Afghan people regarded India as a true friend.
The polls in Afghanistan will end 13 years of rule by Karzai, who has held power since 2001. Preliminary election results are expected on April 24.