China’s Foreign Ministry on Monday said they hope Singapore can respect the “One China Policy” after Singapore’s Prime Minister Lee Hsien Loong sent a letter to Leung Chun-ying, Hong Kong’s Chief Executive, demanding the nine Singaporean Terrex AV81 8×8 wheeled armored personnel carriers the city detained six weeks ago to be returned immediately.

The military equipment was seized en route back home after finishing a routine training in Taiwan on November 23, 2016.

• Hong Kong customs officials seized 9 Terrex AV81 wheeled armored personnel carriers

Carried by the commercial shipping company of APL, the nine cars were scheduled to arrive in Singapore on November 29.

Lu Kang, spokesman for China’s Foreign Ministry, said the “One China Policy” is the basic prerequisite for the country to develop relations with any other countries.

He also said Singapore is expected to comply with the law in Hong Kong.

The Hong Kong government said their investigation is underway and it will take some time.

Singapore’s Defense Minister Ng Eng Hen said the military equipment belongs to the Singaporean government and thus enjoys the sovereign immunity under international law. He said Hong Kong customs’ action went against both its indigenous law and the international law, and the city is due to return the armored personnel carriers.

The Terrex AV81 8×8 wheeled armored personnel carrier was originally developed in Ireland by Timoney for Singapore Technologies Kinetics. Vehicle underwent initial trials in Ireland and United Kingdom and was shipped to Singapore for evaluation in late 2000. Production commenced in 2006. The Singapore Armed Forces acquired at least 135 Terrex armored personnel carriers.