Riyadh/Sanaa, Sep 16 (IANS): Saudi authorities continued investigating the destructive drone attack by Yemeni Houthi rebels against two Aramco facilities earlier this weekend.

The United States and the internationally recognized Yemeni government are accusing Iran of Saturday's attack against Saudi state energy company Aramco, the world's largest oil producer, Efe news reported.

In Yemen, meanwhile, the Saudi-led military coalition is still bombing Houthi positions in the northwest part of the country.

On Saturday night, Aramco CEO Amin H. Nasser visited the site of the attack and reiterated that the company was working to restore production, which has been reduced by 5.7 million barrels per day (bpd) of crude, which is 50 percent of the company's full production.

Aramco emergency teams contained the fires caused by the attack, the company said in a statement.

The attack, which was carried out by 10 drones, has not only had a significant impact on the global economy and the world's oil supply chain, but it has also made a profound mark on international politics, as the United States blamed Iran for backing the Houthis at a time of heightened tensions between Washington and Tehran.

On Sunday, it was also clear that the attack affected the Saudi stock market, as many experts fear that it may complicate the initial public offering (IPO) planned by Aramco, which is considered by the Moody's and Fitch credit rating agencies to be the most profitable company on the planet.

The Yemeni conflict continues to worsen with a series of bombings in the past 24 hours.

Saudi fighters on Sunday attacked Houthi positions near the district of Abs, in the governorate of Hajjah, on the border with Saudi Arabia, turning the area into a battlefield, the Almasirah TV channel, controlled by the rebels, reported.

In the neighbouring governorate of Saada, the main stronghold of the rebels, who are backed by Iran, Saudi fighter jets carried out at least seven bombing runs against two positions, where there were also attacks during the night.

"Fighters flew constantly over the city until dawn and we couldn't sleep due to the bombings," eyewitness Naif Ali told Efe over the phone.

At the political level, the attack has increased tensions between the United States and Iran as Secretary of State Mike Pompeo said "Iran has now launched an unprecedented attack on the world's energy supply."

"We call on all nations to publicly and unequivocally condemn Iran's attacks. The United States will work with our partners and allies to ensure that energy markets remain well supplied and Iran is held accountable for its aggression," Pompeo said on Twitter.

The Houthis claimed responsibility for the attack despite a lack of evidence that proves their claims, Pompeo said.

Yemen's information minister, Muammar al-Aryani, said he agreed with Pompeo.

"Iranian arms in the region go from the realization of an act and logistical support to claim responsibility for the attack. The Houthis claimed responsibility to divert the eyes away from the Tehran regime," al-Aryani tweeted.

Iran's objective is that it not be made to pay for what it has allegedly committed, the minister said.

The Iranian Foreign Ministry, for its part, refuted the accusations, denouncing what it called plans to destroy the image of the Islamic Republic.

In a statement, Iranian Foreign Ministry spokesman Abbas Mousavi called Pompeo's accusation "blind and abortive comments that are obscure and meaningless within a diplomatic framework."

Yemen has been torn by a civil war between Houthi rebels, who currently control the capital Sanaa and other parts of the country, and Saudi-backed government forces since late 2014.