Guaidó, who has declared himself interim president, called on volunteers to help with distribution said his plans would be ready next week.

A government official called aid "a Trojan horse" and said the country had a duty to defend its borders.

He accused US President, Donald Trump, who endorsed the opposition leader, of just wanting to exploit Venezuelan oil.

Meanwhile, an active Venezuelan Army Colonel said he had switched his allegiance to Mr Guaidó, and urged fellow soldiers to allow aid into the country.

In a video circulated on social media, Col Ruben Paz Jimenez said he was now backing Mr Guaidó and that 90% of the armed forces were unhappy with Mr Maduro's government.

The defection comes a week after Air Force Gen. Francisco Yanez pledged his support for Mr Guaidó.

However, so far, most of the armed forces appear to be still loyal to Mr Maduro.

Millions of people have fled Venezuela as hyperinflation and other economic troubles render food and medicines scarce.

Since the outbreak of the current political crisis, Washington has announced sanctions on the Venezuelan oil industry

President Nicolás Maduro, who has the support of the army, rejected letting foreign aid into the country.

Last week, a tanker and cargo containers blocked the Tienditas international bridge, which links Venezuela to its more stable neighbour to the west.

The blockages were still there on Friday, and many soldiers were seen standing guard.