Nicolas Maduro, Venezuela's president, plans to limit the US diplomatic presence in Venezuela and require American tourists to obtain visas, amid growing tensions between the two countries.

Maduro said the measures, announced on Saturday, aimed to "control" US meddling in Venezuelan affairs.

Maduro has intensified his allegations of coup and assassination plans in recent months - often purportedly backed by the US - as he faces 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 was unclear when the plan would be implemented.

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

Diplomatic staff

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

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

Additionally, 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", Maduro said.

Maduro cited former President George W Bush and Vice President Dick Cheney, as well as Hispanic American politicians Bob Menendez, Ileana Ros-Lehtinen and Marco Rubio.

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.

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, Maduro has hardened his speech against the US embassy in Caracas, accusing it of "interference and abuse," and of meeting with the Venezuelan opposition.

The US and Venezuela have been at diplomatic odds since 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 has expelled several US diplomats under Maduro.