BEIJING - China is working on what will be a "substantial" tariff reduction for imported cars, an official said Wednesday, as the country is making more efforts to boost imports and further open up domestic markets.

"We will publish [the new tariffs] as soon as possible after finalizing the details," Chen Yin, chief engineer of the Ministry of Industry and Information Technology, said at a press conference.

China has lowered auto tariffs multiple times since 1986, with the tax rate down from 220 percent to the current 25 percent. The number of imported cars increased 16.8 percent year-on-year to 1.22 million in 2017.

Plans have also been released to remove restrictions on foreign investment in China's auto industry.

"We will scrap caps on foreign shares of new energy vehicle producers this year, and in makers of commercial and passenger vehicles in 2020 and 2022 respectively," Chen said. "Foreign investors will also be allowed to set up more than two joint ventures."

Easier market access in the car industry is part of the country's broader opening-up push.

China has rolled out an array of measures to facilitate imports and is prepared to further liberalize services and sectors, including manufacturing of ships and planes.