The Spanish Supreme Court has dropped European arrest warrants for Carles Puigdemont and five other Catalan politicians.
The former Catalan president and other senior officials have been in exile in other European countries since unilaterally declaring Catalan independence in the wake of a contested referendum.
The independence declaration led to the Spanish government dissolving the Catalan parliament and taking direct control of the region until a new government was sworn in last month.
Mr Puigdemont - who initially fled to Belgium to escape charges from Spanish authorities - faces charges of rebellion in Spain.
International arrest warrants were previously dropped last December, but reissued in late March - a decision which saw Mr Puigdemont arrested after entering Germany.
However, a court in the German state of Schleswig Holstein last week ruled Mr Puigdemont would not be extradited on the accusation of rebellion - and could only be returned to Spain to face the lesser charge of misusing public funds.
The German court ruled that the former Catalan leader's actions did not meet the criteria for the German offences of 'high treason' or 'rioting'.
The decision meant Spanish courts could not try Mr Puigdemont for the more serious charge if he was returned to the country.
'Lack of commitment'
In a ruling published today, Supreme Court judge Pablo Llarena criticised the German court for a 'lack of commitment' in dealing with a case that could have damaged 'the Spanish constitutional order'.
Warrants have also been dropped against five others - Antonio Comin, Luis Puig, Meritxell Serret, Clara Ponsatí and Marta Rovira - who are currently in Belgium, Scotland and Switzerland.
Despite the decision, national arrest warrants remain in place in Spain - meaning the fugitives will be arrested if they enter the country.
In a tweet, Scottish First Minister Nicola Sturgeon welcomed the decision to drop the extradition proceedings for Clara Ponsatí, who is currently serving as a professor in economics at St Andrews University in Scotland.
If true, very good news that extradition proceedings have been dropped against @ClaraPonsati. Political differences should be pursued democratically not through criminal courts. Let’s hope she is now allowed to get on with her life - and being the credit to Scotland that she is. https://t.co/GW46YcDk4h
— Nicola Sturgeon (@NicolaSturgeon) July 19, 2018