China has called on Iran to intervene in the Red Sea shipping blockade by the Iran-backed Houthis, Reuters reports.

The Yemeni militia have disrupted the Red Sea with dozens of attacks in solidarity with Gaza militants Hamas since the Palestinian group declared war on Israel on October 7.

Meetings have allegedly taken place in Beijing and Tehran as China aims to protect its own shipping, threatening that if action isn’t taken by Iran to reign in its proxy, business relations between the two nations will be at risk.

"Basically, China says: 'If our interests are harmed in any way, it will impact our business with Tehran. So tell the Houthis to show restraint'," Reuters quoted an Iranian official briefed on the talks, speaking on condition of anonymity.

The attacks, which began in November, have raised the cost of shipping and insurance by disrupting a key trade route between Asia and Europe used widely by ships from China. The passage is responsible for 12 percent of global trade.

For the last decade, China has been Iran’s biggest trading partner, with Chinese oil refiners buying over 90 percent of Iran’s crude exports last year alone, according to Kpler.

While global sanctions weigh heavily on Iran, China has offered a lifeline, gaining huge discounts in the process, though Iran’s oil only accounts for 10 percent of China’s crude imports.

Though the two nations signed a 25-year economic cooperation agreement in 2021, China has not invested as much as was hoped in Tehran, nor engaged in non-oil trade to the extent envisaged.

Iranian state media says Chinese firms have only invested $185 million since then. State media also said last year that Iranian non-oil exports to China fell 68% in the first five months of 2023 while Iran's imports from China rose 40%.

By contrast, Chinese companies committed last year to invest billions in Saudi Arabia after the countries signed a comprehensive strategic partnership in December 2022.

China has been slowly increasing its influence in the region as was seen in last year’s reinstating of ties between Iran and Saudi Arabia after seven years of tensions, China among the nations facilitating the detente.

However, while China holds sway in Tehran, the situation is complex. Tehran risks backlash from its proxies in Lebanon, Syria and Iraq, which have also been acting in allegiance with Hamas against both Israeli and US targets since the Gaza war began.

China's ministry of foreign affairs told Reuters: "China is a sincere friend of the countries of the Middle East and is committed to promoting regional security and stability and seeking common development and prosperity."

"We firmly support Middle Eastern countries in strengthening their strategic independence and uniting and collaborating to resolve regional security issues," without directly referring to the talks over the Red Sea passage. Iran's foreign ministry did not comment.

The disruption by the Yemeni militia, trained and backed by Tehran, has triggered military strikes by the US and British forces but it has failed to stem the tide.

According to Reuters, a senior US official said Washington had asked China to use its leverage with Iran to persuade it to restrain the Houthis, including in conversations Secretary of State Antony Blinken and National Security Advisor Jake Sullivan had this month with senior Chinese Communist Party official Liu Jianchao.

Iran denied the claims that China had since expressed concerns but on January 14, China's foreign minister Wang Yi called to end the attacks on civilian ships in the Red Sea, though did not name the Houthis or reference Iran.

On Thursday, Houthi spokesman Mohammed Abdulsalam said Iran had not conveyed any message from China about scaling back attacks.

"They will not inform us of such a request, especially since Iran's stated position is to support Yemen. It condemned the American-British strikes on Yemen, and considered Yemen's position honourable and responsible," he told Reuters.

While Tehran claims that the Houthis’ action is independent, in spite of the blockade being called for by Iran’s Supreme Leader himself, the complexity of Iran’s shadow war against Israel and the US continues, and the influence of China yet to be seen.