Here are some of the key reactions after speaker of the Venezuelan parliament Guaido declared himself "acting president" on Wednesday.

- US recognises Guaido -

US President Donald Trump recognised Guaido as acting leader, declaring his National Assembly "the only legitimate branch of government duly elected by the Venezuelan people".

The US said it stood ready to use "all options" if Maduro tries to quash the opposition.

Secretary of State Mike Pompeo warned Maduro against use of force, saying "the time for debate is done" and calling Maduro's regime "illegitimate".

- UK: Guaido 'right person' -

Britain joined the US in declaring that Madura was "not the legitimate leader of Venezuela" and backing Guaido.

"The United Kingdom believes Juan Guaido is the right person to take Venezuela forward. We are supporting the US, Canada, Brazil and Argentina to make that happen," Foreign Secretary Jeremy Hunt said in a statement -- diverting from the cautious approach of other Europe leaders.

- Russia calls Maduro -

Russian President Vladimir Putin called Maduro and expressed "support for the legitimate authorities of Venezuela in the context of a domestic political crisis that has been provoked from the outside," the Kremlin said.

Putin said that any intervention by other countries "violates the fundamental norms of international law", according to the statement.

The Russian foreign ministry warned that support for Guaido was a "direct path to lawlessness and bloodshed".

- China: don't interfere -

China, Venezuela's main creditor, "opposes interference in Venezuelan affairs by external forces", Chinese foreign ministry spokeswoman Hua Chunying told a news conference.

She said Beijing urged calm pending a "political resolution to Venezuela's problem through peaceful dialogue within Venezuela's constitutional framework".

- EU: rule of law -

The European Union reacted cautiously to the fast-moving crisis in Venezuela.

EU diplomatic chief Federica Mogherini in a statement stressed EU support "for the restoration of democracy and rule of law in Venezuela through a credible peaceful political process in line with the Venezuelan constitution".

- France: 'restore democracy' -

French President Emmanuel Macron said Europe favoured "the restoration of democracy", stressing a need for new elections, after what he called Maduro's "illegitimate" election in May last year.

- Spain speaks to Guaido -

Spain's Prime Minister Pedro Sanchez stressed the need for "free elections" in Venezuela in a telephone call to Guaido, the Spanish government said.

Foreign Minister Josep Borrell said an election was the "only way out" of the impasse.

- Neighbours: time up -

Several of Venezuela's regional neighbours said Maduro's time was up.

Brazilian President Jair Bolsonaro said "Brazil will support politically and economically the process of transition so that democracy and social peace return to Venezuela".

Colombian President Ivan Duque said his country was behind Guaido and will "accompany this process of transition to democracy so that the Venezuelan people free themselves of their dictatorship."

Argentina, Brazil, Canada, Chile, Colombia, Costa Rica, Guatemala, Honduras, Panama, Paraguay and Peru issued a joint statement endorsing Guaido as interim president.

- Cuba, Mexico: 'imperialism' -

Cuba and Mexico offered Maduro support however. Cuban President Miguel Diaz-Canel slammed "imperialist attempts to discredit and destabilise" Venezuela.

- UN: 'disaster' risk -

UN head Antonio Guterres appealed for dialogue to avoid "an escalation that would lead to the kind of conflict that would be a disaster for the people of Venezuela and for the region."

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