Yemen's Houthis said on Monday that their forces hit a Saudi oil tanker in the Red Sea with a ballistic missile, as the Iran-backed group continues to pursue a maritime blockade of the Bab el-Mandeb strait, another crucial artery for global shipping.

"The strike was accurate and direct, resulting in a fire breaking out aboard the vessel and causing a number of other ships that were present in the target area to flee," the Houthis said in a statement.

"This targeting comes as part of the implementation of the Armed Forces' decision to ban maritime navigation by the Saudi enemy."

The Houthi claim came hours after a British maritime agency said a tanker struck by an "unknown projectile" caught fire off Saudi Arabia's Red Sea coast.

"The Company Security Officer reported a tanker has been struck by (an) unknown projectile causing a fire to the vessel on the main deck," said the United Kingdom Maritime Trade Operations.