Agreement has triggered protests and main opposition party condemns it as ‘shameful and humiliating’.
Sanchez’s Socialist Party (PSOE) has secured the backing of Junts to form a government after elections in July produced no outright winner.
On Thursday, senior PSOE lawmaker Santos Cerdan announced the deal with the party led by Carles Puigdemont, currently living in exile in Belgium for his involvement in secession efforts in 2017.
“Six years have passed [since the secession attempt] and the conflict is still unresolved,” Cerdan told a news conference in Brussels. “Our goal is to start a new chapter … where the errors of the past are no longer obstacles to overcome.”
An amnesty could exculpate as many as 1,400 activists and politicians involved in the attempt to separate Catalonia from Spain. It has been condemned by Sanchez’s conservative opponents who have organised large protests and accused him of putting the rule of law in Spain on the line for his own political gain.
The conservative main opposition People’s Party (PP), which won the most votes in the July elections but failed to form a government, has attacked the prospect of amnesty for separatists, whom they describe as traitors to Spain.
PP spokesperson Cuca Gamarra said on Thursday that Spain was looking at “a shameful and humiliating deal”.
In the capital Madrid, Alejo Vidal-Quadras, 78, the former head of the PP in Catalonia was shot in the face and hospitalised on Thursday. No arrests have yet been made, police said.
In 2017, separatists in Catalonia, where their cause enjoys substantial support, led an effort to break away from Spain that resulted in a vote and unilateral declaration of independence.
The Spanish government, which considered that move illegal, cracked down and moved to prosecute hundreds of people, from officials like Puigdemont to citizens, for their involvement. When Sanchez first came to power, about half of Catalonians supported independence, and he pardoned several leaders in an effort to defuse tensions and undermine support for separatist parties.
Puigdemont, whose extradition is still being sought by Spanish courts, would benefit from the deal, and rallies have taken place in Madrid over the last week in opposition to amnesty.
Cerdan admitted that his party still had “profound disagreements” with Junts but had put them aside in the interest of creating a “stable government”, with the deal including an agreement for a full four-year term.
PSOE has until November 27 to form a government or fresh elections are automatically triggered.
For now, even with Junts’s support, they are still short of an absolute majority of 176 seats to win a first round vote in the 350-seat congress, or to secure a simple majority in a second vote, with five lawmakers from the Basque Nationalist Party (PNV) saying that they would wait and see the details of the deal.
The agreement could also come under scrutiny from the judiciary, including within the European Union.
EU Commissioner of Justice Didier Reynders sent Spain’s government a request for more information on the deal this week.