Venezuelan president Nicolas Maduro plans to limit United States' diplomatic presence in the country and require American tourists to obtain visas, amid growing tensions between the two countries.

The leftist president said the measures, announced Saturday, aimed to "control" US meddling in Venezuelan affairs.

Over recent months, Mr Maduro intensified his allegations of coup and assassination plans - often purportedly backed by the US - as he faced a deep economic crisis and a sharp drop in popularity.

"In order to protect our country ... I have decided to implement a system of compulsory visas for all Americans entering Venezuela," he told supporters.

Under the new measures, Venezuela will start charging tourists the same visa fees the US asks of Venezuelans, though it is unclear when the plan will be implemented.

But the restrictions could also have an impact on business travellers seeking to invest in one of the biggest oil producing countries.

In his fiery speech outside the Miraflores presidential palace, Mr Maduro noted that Americans had 100 diplomatic staff in Caracas, compared to 17 Venezuelan diplomats in Washington.

He cited the Vienna Convention's principle of the equality of states concerning the size of respective diplomatic missions when ordering his foreign ministry to "reduce, adjust and limit the number of US officials" at the American embassy in Caracas.

The US State Department said it had not received any diplomatic communication regarding a reduction in its embassy personnel or visas.

However, a senior administration official emphasised that Caracas's "continued allegations that the United States is involved in efforts to destabilise the Venezuelan government are baseless and false".

George W Bush, Dick Cheney banned, considered 'terrorists'

Additionally, Mr Maduro singled out several US political figures as being unable to come to Venezuela because his government considers them "terrorists".

"A group of US political leaders who have violated human rights in bombing countries like Syria, Iraq and Afghanistan will not be able to enter Venezuela because they are terrorists," he said.

Mr Maduro cited former president George W Bush and his vice president Dick Cheney, as well as Hispanic American lawmakers Bob Menendez, Ileana Ros-Lehtinen and Marco Rubio.

Mr Maduro said the visa decision was made after the capture of an American pilot of Latin American origin in the western state of Tachira suspected of carrying out "covert" espionage activities.

He did not provide additional details about the previously unreported arrest.

Mr Maduro also warned that the US mission must alert and receive authorisation from the local government for any meeting held by US diplomats in Venezuela.

In recent days, the Venezuelan president hardened his speech against the US embassy in Caracas, accusing it of "interference and abuse" and of meeting with the Venezuelan opposition.

On Monday, he demanded that the "damn Yankees" respect his homeland and called on US president Barack Obama to "rectify" the "chaos" of Washington's policy toward Venezuela.

US secretary of state John Kerry blasted the "egregious behaviour" of Mr Maduro's government, vowing to quickly implement recent sanctions against the country.

The top US diplomat said Wednesday that the Maduro government had made a series of "wrong choices" in its handling of anti-government protests, as well as its clampdown on opposition leaders over claims of a US-backed coup plot.

Washington and Caracas have been at diplomatic odds since Mr Maduro's predecessor Hugo Chavez came to power in 1999, repeatedly criticising US "imperialist" policy.

They withdrew their ambassadors from each other's country in 2010 and Venezuela expelled several US diplomats under Mr Maduro.

In December, the US imposed sanctions on senior Venezuelan officials accused of violating the rights of protesters during anti-government demonstrations at the start of 2014.

AFP