Guaido had risked arrest on his return to Venezuela for flouting a court-imposed travel ban to visit other Latin American countries.
Maduro, meanwhile, pressed his supporters to hold "anti-imperialist" marches Saturday to counter fresh protests planned by Guaido.
Most Western countries, including the United States and Germany, have recognized Guaido as the OPEC nation's legitimate head of state and back his plan to install a transition government ahead of free elections.
Since the start of the year, Venezuela has been shaken by political unrest sometimes erupting in violence after USA -backed opposition leader Juan Guaido announced he was invoking the constitution as head of congress to wrest power from President Nicolas Maduro.
"[I heard from him at] maybe about 6 or 7 yesterday evening and yesterday morning about 10", she said.
European countries should "adopt a constructive balanced attitude" toward Venezuela's political crisis, instead of "encouraging the path of coups and violence (and) facilitate a peaceful and negotiated solution between the Venezuelan camps", it added.More news: 2nd HIV patient in 'sustained remission,' physicians say
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"This is an incomprehensible decision that aggravates the situation and does not contribute to de-escalation", Maas said in a statement.
Authorities in Venezuela have reportedly arrested a U.S. freelance journalist after an early morning raid on his Caracas home by the country's feared military counter-intelligence agency.
An American citizen who working as a journalist in Venezuela has been freed after being detained by security forces early Wednesday.
Venezuela broke off diplomatic ties with neighbouring Colombia after Maduro's security forces blocked a February 23 attempt by Guaido and allies to bring humanitarian aid into Venezuela from Colombia and Brazil.
The U.S.is pursuing new diplomatic and economic initiatives to support Guaido's bid for a transitional government in Venezuela, National Security Adviser John Bolton said Wednesday. Griffith said it's clear Maduro's forces are holding the journalist.
Also on Wednesday, U.S. Vice-President Mike Pence said the U.S. will revoke more visas from prominent Venezuelans as it seeks to increase pressure on Maduro to give up power.