Hundreds of lorries are waiting to get into the city
Hundreds of lorries waiting to bring goods and fuel into the city are lined up either side of a major river crossing in a protest that is part of the ongoing political crisis in the country.
The blockade comes as the opposition candidate in the island's disputed election, Marc Ravalomanana, said he was ready to negotiate with President Didier Ratsiraka.
Speaking after an initial meeting with the president, Mr Ravalomanana told the BBC that the two men had agreed on teams to help with the negotiations.
He said he was prepared to discuss a compromise and build a consensus government.
But Mr Ravalomanana said demonstrations would go on until it was established who had won December's elections.
Madagascar's capital has been rocked by huge daily protests and a general strike over Mr Ravalomanana's claim that he won the poll outright and that authorities rigged the results in order to hold a second round.
Trucks
For a week trucks loaded with supplies for Antananarivo have continued to stack up.
Our correspondent said he counted more than 200 on one side of this major river crossing, on the road between the capital and the main port of Tamatave.
On the other side of the bridge more than 400 lorries with containers and petrol tankers from the port's oil refinery are queuing up waiting to cross.
But a truck is parked across the road, along with felled trees, preventing any vehicles from getting through.
Reaction
This blockade is widely thought to have been put in place by supporters of the incumbent president as a reaction to the general strike in the capital and the mass protests.
There is no demonstration at this blockade and no political supporters on either side.
Our correspondent says the government's and the police's failure to act and remove the barriers suggests this is a ploy by the president to isolate the capital city and his opponent's support base.
The two rivals met for the first time on Wednesday since the crisis began for an initial discussion mediated by Organisation of African Unity chief Amara Essy.
The OAU has called for the second round - scheduled for 24 February - to be postponed to allow "preparation time for a credible election".
President Ratsiraka has already started campaigning ahead of the second round, which he says must go ahead in line with a high court ruling last month.
But the OAU believes that international monitors are required to ensure that a second ballot is carried out fairly and transparently.