Windhoek - Namibia's president on Tuesday declared a state of emergency in areas hit by what he said could be some of the worst floods in recent memory.

"It is with a heavy heart that I declare an emergency for the north-central and north-eastern parts of Namibia," President Hifikepunye Pohamba told reporters.

He said 92 people had drowned since flooding began in early February and 5,032 people had been left homeless in the southern African country.

"Crop fields are submerged in water and I send out an urgent appeal to the international community for assistance ... as the current flood is worse than a year ago and could be one of the worst in recent memory," said Pohamba.

About 100,000 children have been unable to attend classes after the floods forced 218 schools to close.

Floods that struck Namibia at about the same time last year killed 42 people and displaced thousands.