Spain's acting foreign minister said Friday that a Venezuelan anti-government activist is a guest at the Spanish Embassy in Caracas, which can't be turned into a center of political activities.

Leopoldo López, a prominent opponent of President Nicolás Maduro, spoke with reporters Thursday at the gate of the Spanish ambassador's home in the Venezuelan capital and urged people to support opposition leader Juan Guaidó. That brought a rebuke from a Venezuelan diplomat and deepened political tensions between Caracas and Madrid.

Maduro has thwarted the latest coup attempt against his government as opposition leader Juan Guido's call on the military appeared not to have triggered a broader revolt. In a show of defiance Thursday, Maduro took to the streets of Caracas in a march flanked by senior military officers and followed by 4,500 military personnel, according to the Defense Ministry.

The military has so far supported the country's democratically elected President Maduro and refused to back Guaidó, who declared himself interim president in January and has backing from dozens of countries, including most of Latin America and the U.S. Maduro has called Guaidó a U.S.-backed puppet who seeks to oust him in a coup. The government has arrested his top aide, stripped Guaidó of his parliamentary immunity and opened multiple probes. It has also barred him from leaving the country, a ban Guaidó openly violated earlier this year.

Venezuela has been rocked by protests since Jan. 10 when President Maduro was sworn in for a second term following a vote boycott by the opposition. Tensions climbed on Jan. 23 when Guaidó declared himself interim president, but Maduro has so far refused calls to step down.