Spain will increase its troops in Afghanistan after the NATO summit that opens on Friday, the daily El Pais reported.
Spain was expected to enlarge its contingent in NATO's 62,000-strong International Security Assistance Force (ISAF) from 780 to more than 1,000 soldiers, reported dpa.
Spain would make the move in support of an expected US strategy of gradually transferring responsibility for Afghanistan's security to the Afghans themselves, the daily said.
Spain had been expected to increase the number of troops in Afghanistan partly in compensation for its decision to withdraw its 620 soldiers from Kosovo, which sparked criticism from the United States and other allies.
Foreign Minister Miguel Angel Moratinos announced Friday that Spain was sending a new "small" contingent to Afghanistan to train a battalion of the local army.
The government was also considering sending paramilitary Civil Guard police officers to train Afghan security forces, Moratinos said.