In Ankara, Turkish Foreign Minister Mevlut Cavusoglu said recognising a leader other than Maduro might cause "chaos".
They have called for a nationwide demonstration Wednesday, urging Venezuelans - especially members of the armed forces - to abandon Maduro.
Guaido, on being sworn in as the assembly president earlier in the month, called on the military and the public to support a transitional government to restore democracy after declaring Maduro's presidency illegitimate.
Officials said 25 soldiers were quickly caught at the National Guard outpost 3 kilometres (2 miles) from the Miraflores presidential palace, and two more arrests were made at another location.
The military, in a statement, said that it had recovered all the weapons and captured those involved in what it described as "treasonous" acts motivated by "obscure interests tied to the far right".
Vice President Pence reiterated the American people's commitment to seeing democracy prevail.
For the past two weeks, ever since Maduro took the oath for a second six-year term in the face of widespread worldwide condemnation, the newly invigorated opposition had been preparing for nationwide demonstrations Wednesday coinciding with the anniversary marking the end of Venezuela's last military dictatorship in 1958. Troops fired tear gas to disperse them.
Rooney: United should go "all out" for Pochettino
There were reports of dressing-room unrest prior to Mourinho's sacking amid a fractured relationship with star midfielder Paul Pogba .
U.S. President Donald Trump formally recognised Guaido shortly after his announcement and praised his plan to hold elections.
Venezuela's vice president on Tuesday accused her United States counterpart of "openly calling for a coup d'etat" ahead of a mass street protest announced by the opposition for Wednesday.
"Do you want to be a country colonized by the gringos?" he asked the crowd of several hundred seated before him. "We need a political change, because we don't have any water or electricity", said Angel Rivas, a 49-year-old labourer at the protest.
Today's protests come 61 years to the day since Venezuela emerged from military dictatorship and will likely be characterised by sporadic violence and clashes with security forces.
They allegedly stole weapons from a security post in the capital, Caracas, and took four officers hostage before making their way to Cotiza in the early hours of Monday.
In the Chacao district of eastern Caracas, a traditional opposition bastion, a dozen protesters spoke of a renewed confidence in dislodging Maduro and predicted a new wave of demonstrations.
The increasingly authoritarian Nicolas Maduro-led government, continuing the policies of Hugo Chavez, denies the existence of a humanitarian catastrophe, instead pointing fingers at everything from Venezuela's positioning to the sun, to opposition movements and the United States for infringing on their economic rights.
In 2016, Maduro lost control of the National Assembly, enabling the opposition to challenge his leadership, but the loyalist-dominated Supreme Court stripped the legislature of its powers in 2017.