Spain' defence minister will appear in parliament in Friday to give details on how the country will participate in a US-led coalition to stamp out Isis.
Spain's chief contribution will be the sending of 300 troops to Iraq, El País newspaper reported on Friday.
The Spanish government will also allow coalition forces to use the US military bases of Rota and Morón de la Frontera in its operations.
Previously, foreign minister José Manuel García-Margallo said that Spain's contribution to the fight against Isis would include supply of lethal weapons, information gathering, and in-flight refuelling of aircraft.
But he ruled out the sending of combat troops and has also said it won't participate in aerial bombings of the country.
The arrival of 300 troops in Iraq will be the first time Spanish troops have been present in the country in a decade.
Spain's involvement in the Second Gulf War was hugely contentious domestically and had a major bearing on the results of the country's 2004 general elections.
A terrorist attack in Madrid on March 11th, 2004, just three days before Spanish voters went to the polls, killed a total of 191 people on two suburban trains.
Spain's conservative Popular Party government of the time initially blamed the attacks on the Basque separatist group ETA. But many Spaniards believed they were trying to deflect attention from a possible link between the bombings and Spain's involvement in the Iraq War.
The Popular Party lost the general elections and a socialist PSOE government took power, subsequently withdrawing Spanish troops from Iraq.
Spain is currently also fighting Isis closer to home, working with Moroccan authorities to break up cells dedicated to recruiting jihadists for the fight in Iraq and Sierra.
In later September Spanish and Moroccan security forces detained Mohamed, a Spanish national of Moroccan descent, and eight other suspected members of the cell on Friday in the Spanish enclave of Melilla in North Africa and the nearby Moroccan town of Nador.
On Wednesday, French anti-terror police said they would investigate after reports said eleven members of one family including the grandmother and six-month-old baby, have left the country bound for Syria in the hope of joining Isis extremists.
On the same day, 1,300 police officers were deployed in the German city of Hamburg to prevent violence re-erupting between local Kurds and Muslim fundamentalists.
More than 1,000 Kurds took part in a peaceful demonstration against Isis violence against Kurdish cities in Syria, especially the Syrian-Turkish border town of Kobane.
But some of the demonstrators returned to the St. Georg district, scene of the Tuesday night street battles in which 14 people were injured, and began throwing bottles and stones, police said.