A Saudi-led military coalition intervened in Yemen on March 26, 2015 to restore the government of President Abedrabbo Mansour Hadi after the Iran-backed Huthis and their allies took over large parts of the country including the capital Sanaa.

Sanaa's Sabaeen Square on Monday was a sea of Yemeni flags, with a smattering of posters bearing pictures of Huthi leader Abdulmalik al-Huthi and the slogan "three years of aggression".

Rebel authorities ordered all schools and government offices shut for the anniversary.

Speakers blasted out a fiery speech of Lebanese Hezbollah leader Hassan Nasrallah -- the powerful Shiite group allied with the insurgents -- in which he praised the "steadfastness" of the Yemeni people.

On the stage, male dancers dressed in traditional clothing with rifles hoisted on their shoulders performed for the crowd, broadcast on a massive screen.

"No one can speak on behalf of the Yemeni people. People taking to the streets today is the real voice," Ibtisam al-Mutawakel, head of the rebel cultural committee, told AFP.

"As for the missiles, those are the message of our army and popular committees to the enemy," Mutawakel added, referring to the Huthi-aligned military brigades and paramilitaries.

- Missile attack -

About 10,000 Yemenis have been killed and 53,000 wounded since the start of the coalition intervention in Yemen, which triggered what the United Nations has called the world's worst humanitarian crisis.

The rebels remain in control of the capital, north Yemen and the country's largest port.

Hadi's forces have controlled southern Yemen since 2015, but cracks have surfaced this year between the president and his southern separatist allies.

The rebels have periodically fired missiles into Saudi territory and Saudi forces announced Sunday night they had intercepted seven more, including over Riyadh.

The Huthis confirmed they had launched the attack via their Al-Masirah television. Among the reported targets was Riyadh's King Khalid International Airport.

Saudi authorities said an Egyptian citizen was killed by falling shrapnel in the capital Riyadh.

"This aggressive and hostile action by the Iran-backed Huthi group proves that the Iranian regime continues to support the armed group with military capabilities," coalition spokesman Turki al-Malki said.

The Huthis in November targeted Riyadh airport in what Saudi authorities said was a foiled missile attack, triggering a total blockade on Yemen's ports and international airport.

The blockade was later eased under international pressure.

Allies of Saudi Arabia have also accused Tehran of providing the Huthis with missiles, and Britain on Monday urged Iran to "stop sending in weapons which prolong the conflict, fuel regional tensions, and pose threats to international peace and security."

- US 'directing' war -

Multiple rounds of UN-brokered talks between the warring parties have failed and UN special envoy to Yemen Ismail Ould Cheikh Ahmed threw in the towel last month.

At Monday's rally, Saleh al-Sammad -- head of the Sanaa-based supreme political council -- said the rebels were "ready to reach an understanding" to end the intervention and lift a longstanding siege.

He appealed to Saudi Arabia and its key ally the United Arab Emirates to "seize the opportunity" to achieve peace after the arrival of the new UN envoy, Martin Griffiths, over the weekend.

But Hadi's government released a statement Monday calling the overnight attacks on Saudi Arabia "an open rejection of peace".

Rebel leaders in recent days have sought to highlight the role of the United States in the Saudi-led intervention.

"It is the Americans who are directing this aggression, and participating directly on a number of fronts," Sammad told the rally in Sabaeen Square.

"The position of the Senate proves that this was an American aggression from the first shot," he said.

The US Senate last week rejected a bipartisan bid to end American involvement in Yemen's war, voting down a rare effort to overrule presidential military authorisation.

The US has provided weapons, intelligence and aerial refuelling to the Saudi-led coalition.

The United States formally approved defence contracts totalling more than $1 billion with Riyadh on Thursday, during a high-profile American tour by Saudi Crown Prince Mohammed bin Salman.

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