Shelling from Yemen has wounded two people in southern Saudi Arabia, the kingdom's civil defence agency said late Thursday, in a rare breach of calm along the border.

The civil defence's Twitter account said the shelling occurred in the Tawal area of Saudi's Jazan region, without providing further details.

Dozens of civilians and Saudi soldiers were killed in fire from Yemen along the border after a Saudi-led military coalition launched operations in March 2015 against Iran-backed Houthi rebels who overran much of Yemen.

The Houthis are allied with elite troops loyal to Yemen's former president Ali Abdullah Saleh.

The border has been relatively calm since March when local tribes brokered a truce.

United Nations-mediated peace talks between the government of President Abd-rabbo Mansour Hadi and the rebels started two months ago in Kuwait.

Negotiations have so far failed to achieve a major breakthrough.