An explosion hit a speed boat that Maldives President Abdulla Yameen was travelling in on Monday, but he was unhurt.

It was not immediately clear what caused the blast, which occurred off the capital island of Male.

"The president is unharmed," his spokesman Ibrahim Muaz told reporters, giving no further details about the incident.

Reporters were at the presidential jetty to receive Yameen, who had landed a few minutes earlier at the nearby Hulhule airport after a a visit to Saudi Arabia.

Witnesses said they saw an ambulance rush to the jetty and police immediately cordoned off the area.