Spain's acting Prime Minister, Pedro Sanchez, said he supported granting a controversial amnesty to those involved in Catalonia's failed 2017 independence bid in the hope of persuading the region's parties to back him in government.
"In the interest of Spain, in defence of coexistence among Spaniards, I defend today the amnesty in Catalonia for the events of the past decade," Sanchez said during a meeting of the Socialist Party's Federal Committee in Madrid.
The announcement was met with applause and a standing ovation from those present.
Sanchez, who is trying to form a coalition government three months after an inconclusive election, agreed a coalition deal with the left-wing Sumar this week, but support from that party's 31 lower-house lawmakers is not enough to secure the premiership.
He needs the backing of Catalan separatist parties, Esquerra Republicana de Catalunya ERC and Junts, who have demanded an amnesty law that could cover more than 1,400 people involved in the failed independence bid.
They have said their support also depends on another independence referendum.
"To continue moving forward, we must overcome all the episodes that in the past divided us and fractured our societies," Sanchez said.
He said his party "looks at the problems head on", adding that 80 per cent of Catalans supported an agreement on the issue.
The potential amnesty has unleashed a political storm in Spain, with mainly conservative opponents holding large protests and accusing Sanchez of jeopardising the rule of law for his political gain.
A poll in September showed 70 per cent of respondents - 59 per cent of them socialist supporters - were against an amnesty.