The unannounced visit by Rajoy, accompanied by his defence minister Pedro Morenes, is his first to the country since his right-wing government came to power a year ago.

The number of Spanish soldiers deployed in Afghanistan stands at 521, with the process of withdrawal already under way, the Spanish daily El Pais reported. All NATO combat forces are due to leave the country by the end of 2014.

After visiting Spanish troops stationed at the NATO headquarters in Kabul, Rajoy was due to head to Herat in eastern Afghanistan where there is a Spanish logistics base before heading on to the Qala-i-naw base in the northeast.