Saudi Arabia said it had intercepted several ballistic missiles fired by Yemeni Houthi forces towards Saudi cities on Friday ahead of a gathering of finance ministers and central bankers from the Group of 20 major economies in Riyadh, reported Reuters.

The Iranian-aligned armed movement launched the missiles from the Yemeni capital Sanaa at 12:30am, Saudi news agency SPA quoted the spokesman of the Saudi-led coalition in Yemen as saying. It gave no further details.

A Houthi military statement said the group had successfully attacked Saudi Aramco and sensitive targets in the Red Sea port city of Yanbu using drones and ballistic missiles, without providing evidence.

Aramco, the kingdom’s state-owned oil company, declined to comment.

The G20 meeting, at which finance officials are due to discuss the global economy, continued as scheduled. It was unclear if any of the projectiles had been fired towards Riyadh, which has been targeted previously.

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An escalation of violence in Yemen since the start of the year has shattered more than three months of calm in the five-year-old conflict, widely seen as proxy war between Saudi Arabia and its regional foe Iran.

Saudi Arabia has been holding informal talks with the Houthis since late September about de-escalation. Riyadh had significantly reduced its air strikes in Yemen and the Houthis had halted missile and drone attacks on Saudi Arabia.

But violence resumed on northern frontlines in January and led to renewed Houthi missile strikes, the first since attacks on Saudi oil facilities in September knocked out more than half its crude output. The Saudi-led coalition resumed retaliatory bombings.

The escalation endangers months of peace efforts by Saudi Arabia and the United Nations, and highlights the challenge Riyadh faces in trying to exit a costly and unpopular war.

The Saudi-led coalition intervened in Yemen’s civil war in 2015 to try to restore the internationally-recognised government of President Abd-Rabbu Mansour Hadi, ousted by the Houthis in Sanaa in 2014.

The war, a military stalemate, has killed tens of thousands of people, most of them civilians, and left millions of Yemenis facing starvation.

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