Venezuela's ambassador to Britain has said his country is unable to cope with the scale of last week's floods and mudslides which killed thousands and left many more homeless.

Roy Chaderton-Matos told the BBC that search and rescue equipment, tents and blankets, and supplies of food and medicines were urgently needed.

He said the most pressing concern was to provide shelter for the hundreds of thousands of survivors.

"It's a mega catastrophe," he said. "We never saw ourselves as a catastrophe country ... And all of a sudden we have this massive tragedy.

"There are entire populations covered by mud, rubble, water. It's growing and growing, every day, it changes hour by hour."

The ambassador said the full extent of the damage had yet to be realised, but described the disaster as unprecedented in recent Venezuelan history.

On the ground, there is chaos and confusion as thousands of people stream out of the worst-hit coastal areas, having lost their homes, their possessions, their families and friends.

Aid effort

Officials have conceded that Venezuela, a poor country despite its vast oil resources, is ill-equipped to handle a disaster of such magnitude. Nations from around the world have rushed in aid.

The US has pledged $3m to the relief effort and has already sent 10 military helicopters, four C-130 aircraft, a patrol boat and almost 100 servicemen.

Tonnes of food and medicine and other emergency supplies have arrived from other countries.

Brazil, Cuba, France, Mexico and Spain have all sent supplies and personnel to help in the massive rescue and relief operation.

The UK Government has made an initial contribution of £500,000 ($800,000), and says it is continuing to monitor the situation.

Meanwhile, rescuers are frantically trying to reach the estimated 150,000 survivors left without shelter.

But housing them and keeping them healthy is proving an uphill battle.

Carel De Rooy, South America representative for the United Nations Children's Fund (Unicef), said Venezuela needed help in preventing the outbreak of epidemics.

"We are looking at water supplies, sanitation, disposal, waste management in the shelters, particularly where 150,000 people will be concentrating," he said.

A Unicef spokesperson in London said other key areas of activity would be public health education, trauma counselling, reuniting families and resettling the homeless.

The UN Office for the Co-ordination of Humanitarian Assistance has said priority needs for Venezuela include blankets, towels, clothing for children, large tents, canned food, generators and portable toilets.