The two vessels were identified as CNS Chang Cheng and CNS Chang Xing Dao on the Malaysian Navy’s social media account.

But a Chinese source provided more information about the two vessels. They were identified as Chang Cheng 271, a submarine, and Chang Xing Dao 861, a submarine support ship. Both ships belong to the North Sea Fleet of the PLAN and were returning from a mission in the Gulf of Aden. During their stay at Kota Kinabalu, the vessel’s officers met with the commander and officers of the Naval Region Command 2 and political leaders of Sabah, invited Malaysian sailors on board the Chang Cheng 271 and held a ceremony on the dock of Chang Xing Dao 861.

While there has been a history of PLAN port calls in Malaysia, this was the first PLAN submarine to visit a Malaysian port. But this is not the first time Chang Cheng and Chang Xing Dao have appeared together. Back in 2009, both vessels visited Sri Lanka. Chinese submarine visits to foreign ports are rare (or rarely reported openly) because submarines signify stealth warfare and are much more sensitive and secretive in nature. The visit by CNS Chang Cheng is therefore important in a symbolic sense, signalling that Malaysia has earned China’s trust despite the ongoing South China Sea dispute.

This CNS Chang Cheng visit, according to the same Chinese source, was mooted during the visit to Malaysia by PLAN Commander Admiral Wu Shengli back in November 2015. The then Malaysian navy chief admiral Abdul Aziz Jaafar proposed that PLAN vessels, including submarines, were welcome to dock at Kota Kinabalu for supply and replenishment, an offer that Admiral Wu accepted.

Two months earlier, three PLAN vessels were in the Straits of Malacca conducting a combined exercise with the Malaysian military. And in November 2016, Malaysia announced that its navy would procure four littoral mission ships from China, the first significant military procurement of its kind between the two countries. The submarine visit is the latest episode not only of intensifying Sino–Malaysian naval cooperation, but also of a burgeoning Sino–Malaysia bilateral relationship. Malaysian Prime Minister Najib reportedly said on several occasions that bilateral ties have hit a ‘historical high’ during his visit to China in October–November 2016.

But the growing Sino–Malaysian ties have come under increasing scrutiny in Malaysia. Ever since two Chinese state-owned enterprises (China General Nuclear Power Corp and China Railway Engineering Corp) stepped in to rescue the debt-ridden 1Malaysia Development Berhad (1MDB) — a government-owned development company — in late 2015, Chinese investments in Malaysia have been portrayed by Najib’s opponents as facilitating the political survival of Najib and the ruling regime.

Najib’s 2016 visit to China, for example, brought back 14 commercial agreements amounting to more than 144 billion Malaysian ringgit (about US$33 billion). But Najib soon found himself needing to defend his China policy against critics who accused him of selling out the country to China. More recently, two heavyweight leaders of the newest Malay-based opposition party Bersatu — former prime minister Mahathir Mohamad and former deputy prime minister Muhyiddin Yassin — also spoke out against Chinese investment as benefiting only Najib and his government and not the Malaysian people. Their criticisms drew a swift rebuke from the Chinese embassy in Malaysia.

These are signs that Sino–Malaysia relations can no longer be insulated from domestic politics in Malaysia. In past elections, the country’s foreign relations were not a major campaign issue. In fact, when the ‘China card’ has been played previously, it was always a ‘positive China card’, whereby the ruling coalition used a good relationship with China to draw support from ethnic Chinese voters. In the upcoming election there is a good chance that the ‘China card’ may be played negatively for the first time, especially by opposition parties such as Bersatu who seek to arouse dissatisfaction among rural Malay voters.

China also faces a dilemma. When Najib approached China for more investment, China saw this as a good opportunity to cement a relationship with a key Southeast Asian country. But China is also being criticised for investing too much into the relationship with Najib and his allies, to the extent that the Sino–Malaysia relationship now seems to be based on, and driven by, Najib’s personal agenda. Any threat to the prime ministership of Najib could therefore become a threat to Sino–Malaysian ties. There is a real risk that Chinese investment projects could be suspended or delayed if Najib is forced out of power or if the opposition wins.

To avoid this, China cannot simply dismiss concerns pointed out by critics of its investments and must be transparent in its economic dealings with Malaysia.

Ngeow Chow Bing is Deputy Director of the Institute of China Studies at the University of Malaya.