Bogota, Feb 15 (IANS): Colombia's annual carnival in the port city of Barranquilla has started with its traditional "Battle of Flowers".

Thousands of tourists and Colombians, including President Juan Manuel Santos, attended the opening ceremony Saturday, Xinhua reported.

Santos stressed on the importance of the carnival, the country's largest cultural event.

"I am very pleased to be here. You know I do not miss this carnival," the president said. "It is a wonderful cultural expression that we Colombians have".

The four-day carnival will also host the Great Parade of Tradition, the Comedy Festival and the Orchestras Festival in the Romelio Martinez Stadium Monday.

Around 1.5 million people are expected to attend the event, with over 13 Colombian artistic expressions carried out by 650 ethnical and cultural groups.

The Barranquilla carnival, one of the oldest and most recognised cultural events in Colombia, was listed as an "intangible cultural heritage" by UNESCO in 2003.