Venezuela has closed its border with Brazil as a row over foreign humanitarian aid continues.
President Nicolás Maduro who announced this on TV say he is also considering shutting the border with Colombia to stop the opposition from bringing in relief.
He has denied any crisis and called the aid delivery plans a US-orchestrated show. Mr Guaidó declared himself interim leader during anti-government protests last month and is recognised by dozens of foreign states, including the US.
Scuffles broke out and tear gas was fired when the convoy of buses and cars was briefly stopped by security forces on a road near Mariara, west of Caracas, but they later moved on.
