Spanish Prime Minister Mariano Rajoy is holding talks with the Catalunya President Artur Mas in Madrid on Wednesday.
Their meeting is seen as the last chance to resolve a bitter dispute over Catalunya’s plans to hold a referendum on independence in November.
Rajoy considers any referendum illegal and violating Spain’s Constitution, drawn up in 1978.
Mas insists he can’t negotiate until Madrid allows Catalans a right to self-determination.
A recent opinion poll shows more than 62 percent of Spaniards think the Constitution should be reformed to devolve more power to the country’s 17 regions
The meeting comes hot on the heels of revelations that the former president of Catalunya and founder of modern Catalan nationalism, Jordi Pujol, held a fortune in undeclared money in secret foreign bank accounts for decades.
Pro-independence sentiment in Catalonia has grown greatly in recent years, with many Catalans feeling they deserves better economic and political treatment from Madrid.