KABUL: Rebuilding agriculture can boost confidence in Afghanistan's fragile government and pull farmers away from the drug money that fuels the Taliban insurgency, the US agriculture chief said on Sunday.

The Obama administration sees agriculture as the biggest non-security priority in Afghanistan, said Agriculture Secretary Tom Vilsack, who arrived in Kabul yesterday for a three-day trip aimed at showing US commitment to the sector.

With 80 percent of income generated from agriculture and only half of the country's arable land currently used, Vilsack said there was "tremendous upside" although he conceded the challenges were huge.