China and Iran are scheduled to stage unprecedented joint naval drills in the strategic Persian Gulf, underlining the close ties between the two countries and China's expanding role in the security of the Gulf region.

Two Chinese warships, guided-missile destroyer Changchun and frigate Changzhou, are to train with their Iranian counterparts during their five-day port call to Iran's southern port city of Bandar Abbas in Hormuzgan Province. The two vessels, which just completed an  anti-piracy mission in the Gulf of Aden and Somali waters, docked in Bandar Abbas on Saturday, the first port call by Chinese naval vessels to Iran.

China's Ministry of National Defense (MOD) Monday confirmed to the Global Times the drills would be going ahead, after Iranian media first broke the news Sunday.

According to the MOD, the vessels will practice exchanging information and operational capabilities with Iranian warships.

According to Iran's Fars News Agency (FNA), Iranian Navy Commander Rear Admiral Habibollah Sayyari Monday said the drills will take place on Wednesday.

The presence of a Chinese navy flotilla in Bandar Abbas is indicative of solidarity between the two nations and militaries, Hormuzgan Governor General Jassem Jadari Sunday said in a meeting with the commanders and crew members of the Chinese flotilla, reported FNA.

"Hormuzgan Province is of particular importance due to its strategic status and its location near the Strait of Hormuz and also the presence of flotillas of different countries in there," the governor was quoted as saying.

Bandar Abbas occupies a strategic position near the Strait of Hormuz, through which a fifth of the world's oil is shipped. Tehran has frequently threatened to close off the strait due to tensions with the West over its nuclear program.

The US Fifth Fleet is headquartered in nearby Bahrain.

However, the MOD has played down the significance of the drills, noting it has been routine in recent years for Chinese warships to make "friendly visits" to countries and hold joint exercises with their navies after the conclusion of anti-piracy missions.

Tang Zhichao, a research fellow with the Institute of West Asian and African Studies at the Chinese Academy of Social Sciences, told the Global Times the joint drills are a result of China's expanding role in Middle East security.

Over the past few years, the Chinese navy has been moving out into blue waters by participating in the anti-piracy missions in the Gulf of Aden.

"As China's economy grows, its security interests in the Middle East and strategic maritime passages such as the Persian Gulf are of growing importance to China. Therefore, military cooperation with Gulf states, including Iran, is increasingly critical," said Tang.

Security in the Gulf region has been dominated by the US. However, in Tang's view, as the West's capability and will to maintain regional security weakens, Gulf regions are looking to other world powers such as China to step in.

The joint exercises also demonstrate the close ties between China and Iran.

China is Iran's largest trade partner, of which Iran's crude oil exports occupy a significant share.

The interim agreement over Tehran's nuclear program signed by Iran and P5+1 countries last November led to decreased economic sanctions on Iran, temporarily alleviating pressure on China's imports of crude from Iran - before that, China was often accused of buying oil from Iran despite the sanctions.

However, with the November deadline for a final agreement looming, there are uncertainties over China's energy cooperation with Iran, a key part of bilateral relations.

Hua Liming, China's ambassador to Iran from 1991 to 1995, told the Global Times that a final accord is unlikely to be signed by November, as neither the US nor Iran can compromise further due to domestic pressure.

"But I don't expect a collapse of the talks either, because both sides have too much at stake and can't afford a collapse. The most probable result is a continuation of the talks even after the deadline," Hua said.

For China, a possible new round of sanctions against Tehran being considered by the US Congress will impose unfavorable conditions for its imports of crude oil, said Hua.

"Iran's relationship with the West is a double-edged sword for China," said the former diplomat. "If relations further deteriorate, China, which is caught between them, won't be in a comfortable spot. However, if Iran mends ties with the West, it will find more alternatives to China in the market."

Last year, US President Barack Obama made an ice-breaking phone call to Iranian President Hassan Rouhani.

In April, Iran tore up a $2.5 billion deal with China National Petroleum Corporation for the Azadegan oil field, fueling speculation that Tehran was trying to bring back Western investors due to eased sanctions.

Hua acknowledged that once Western companies are back in the Iranian market, Chinese companies will be in a disadvantaged position as they lag behind Western counterparts in oil exploration and drilling techniques.