Longtime residents are being pushed out of apartments to make way for tourists in the U.S. and Europe.
Josep Borrell says his nation's move is the only thing averting an economic crisis in the northeastern region of the country.
Catalonia's Parliament voted for independence Friday morning, prompting widespread celebration in the region and immediate rebuke from the Spanish government.
Catalonia's lawmakers are scheduled to meet Thursday to debate Spain's plan to take direct control of the autonomous northeastern region.
Protesters fill the city's downtown to oppose the Catalan government's push for independence from Spain.
Rallies in Madrid and Barcelona are aimed at pushing lawmakers in both cities to end months of silence.
For the Spanish region, the struggle for independence is far from over, but many see the vote as an important step in the face of violent opposition.
Truthdig correspondent Donald Kaufman films a rally in Barcelona on Monday as Spain grapples with the results of Sunday's independence referendum.