The United States and some 50 other countries have recognized Guaido as the legitimate leader of Venezuela, arguing that Maduro's re-election previous year was invalid - partly because popular opposition candidates were barred from running. It gave Kriener 48 hours to leave the country.
He had greeted Guaido at Caracas airport on his return to the country on Monday.
After the expulsion order, German Foreign Minister Heiko Maas said he had made a decision to recall Kriener to Berlin for consultations.
German Foreign Minister Heiko Maas said that kicking Kriener out only "aggravates the situation". "Our, Europe's, support for Juan Guaido is unbroken".
In a speech at the National Assembly, Guaido condemned the expulsion of the ambassador. With both political factions holding firm amid increasing deprivation for Venezuelans, some analysts speculate that they might be considering negotiations on an end to the standoff.
Maduro called Guaido a USA puppet and accused Washington of plotting an invasion. On Tuesday, he will meet with representatives of trade unions, but the venue is not named. There was no immediate comment from Maduro's government, which sought to focus the public's attention on Carnival festivities Monday and Tuesday.
U.S. Sen. Marco Rubio, an influential voice in advocating U.S measures against Maduro, warned that the Venezuelan government could still act against Guaido in ways that it has refined against other opposition voices.
Venezuela is in the midst of an economic upheaval after four years of recession that have plunged many into poverty.
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The U.S. State Department said it is deeply concerned about reports that a U.S. journalist was detained.
The move brings to more than 250 the number of Venezuelans targeted by U.S. visa bans, a State Department official told AFP.
Venezuela broke off diplomatic ties with neighboring 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. It is also unclear where Guaido spent the previous night, however government supporters believe it was the embassy of a Western state. The Trump administration refused to obey Maduro's order.
Guaido flouted a travel ban to tour Latin American countries to muster support for his plan for a transition government ahead of free and fair elections.
Turkey, Russia, Iran, Cuba, China and Bolivia reiterated their support for Maduro, who vowed to cut all diplomatic and political ties with the U.S. Maduro insists he is a victim of a U.S. -orchestrated coup amid a spiraling economic and humanitarian crisis in the country.
As part of his challenge to President Maduro, Juan Guaido is attempting to take control of the state bureaucracy, which he considers to have been "kidnapped" through blackmail and persecution.
Washington continued to tighten the screws on its campaign of sanctions to force Maduro from power, revoking the visas of 77 people linked to the regime, including officials and their families.