Around 90,000 people are stranded in the capital of the north-eastern Beni province, reports say.

The situation could grow worse if rising floodwaters overflow a dyke surrounding the city, officials say.

At least 35 people have died and 350,000 have been affected by the worst floods to hit Bolivia in 25 years.

The president, Evo Morales, said that the government had instructed the civil emergency authorities to plan for the city's evacuation.

"We have instructed the authorities to draft a plan to evacuate Trinidad in case the water keeps rising" Mr Morales said during a trip to the central Cochabamba region, according to the state news agency ABI.

"If the water flows over the dyke, the whole of Trinidad will be washed away."

Financial cost

Trinidad is surrounded by a roadway that acts like a dyke protecting the city from floods.

Residents point out that currently the water is rising by two inches (5cm) a day and the over-flowing is inevitable.

Reuters news agency reports that hundreds of people have already abandoned their homes and are seeking refuge outside Trinidad, in tents, churches and schools.

The unexpected flooding is said to have been caused by the climate anomaly El Nino.

At least 350,000 people in the country have been affected by months of heavy rain, which has caused widespread flooding, mudslides and blocked access to emergency aid.

The flooding has also destroyed close to half a million acres of agricultural land and crops, and resulted in millions of dollars in losses.