Maduro refused all economic assistance as he denied there is a crisis in Venezuela and he even claimed the aid was part of a coup organised by the White House to topple him.
The armed forces have continued to support Mr Maduro, which is why there have been problems in aid entering the crisis-stricken country.
Guaido has argued that US-backed medicine and food must be allowed inside the country, but Maduro claimed it would lead towards US military intervention.
Venezuela’s opposition supporters took to the streets today to demand humanitarian aid is allowed inside the country.
The rallies occurred three weeks after the opposition leader Mr Guaido invoked a constitutional provision to assume the presidency, arguing that Maduro’s re-election last year was a sham.
Most Western countries, including the US, have recognised Guaido as the country’s president.
Experts have warned that eight of ten children in the South American country are at risk of malnutrition due to the food shortages.
Earlier this week, Guaido tweeted: “Today we delivered the first donation, or the first cargo of humanitarian aid, albeit on a small scale, because you know they have blocked the border for the time being.”
The UK has announced it will provide an emergency aid package of £6.5 million to Venezuela.
International Development Secretary Penny Mordaunt said: “I am deeply disturbed by the awful scenes of suffering in Venezuela as a result of the Maduro regime’s reckless mismanagement, with families resorting to eating rotting food to try to survive.
“UK aid will provide life-saving treatment to malnourished children, immunisations against deadly diseases and access to clean water and sanitation.
“While the UK has stepped up by providing urgent relief, all parties must immediately recognise the severity of the crisis and allow unhindered access for aid agencies.”