Mainland Chinese and Hong Kong stocks retreated on Monday as automobile shares slid on price war concerns and Apple suppliers dropped on potential US tariffs.

In Hong Kong, the benchmark Hang Seng Index lost 318.93 points, or 1.35 percent, to end the day at 23,282.33.

The Hang Seng China Enterprises Index fell 1.7 percent to end at 8,437.64 points while the Hang Seng Tech Index fell 1.7 percent to end at 5,157.65.

Carmakers slipped, weighing on both onshore and offshore markets, after BYD slashed prices on some of the models to spur sales as competition heats up.

Its Hong Kong-listed shares dipped 5.9 per cent, while rival Geely Auto tumbled 9.5 per cent.

The CSI All Share Automobiles Index lost 2.9 per cent, the biggest single-day drop in five weeks, while the Hang Seng Automobile Index in Hong Kong tumbled 4.9 per cent.

"The price cuts could put some short-term pressure on earnings," analysts at Sinolink Securities said in a note.

"It got investors concerned about profitability, and the sector is likely to enter a correction."

Apple supplier stocks also lost some ground after US President Donald Trump threatened tariffs on imported iPhones.

iPhone assembler Luxshare lost 0.2 per cent.

Chinese stocks closed lower, with the benchmark Shanghai Composite Index down 0.05 percent at 3,346.84.

The Shenzhen Component Index closed 0.41 percent lower at 10,091.16.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, lost 0.8 percent to close at 2,005.26.

Tokyo stocks closed higher on news that the United States had agreed to delay the tariff imposition on EU goods.

The benchmark Nikkei stock index, the 225-issue Nikkei Stock Average, closed at 37,531.53, up 371.06 points, or 1 percent.

However, China's yuan has strengthened past the 7.17 level after the central bank tightened the midpoint fixing, and analysts say the firming trend of the currency should lend support to the nation's stocks.

"We estimate every 1 per cent of RMB increase versus the USD could boost Chinese equities by 3 per cent," Goldman Sachs' China equity strategist Kinger Lau wrote in a note.

Sectors such as consumer discretionary, property, and brokers typically outperform when the yuan appreciates, he added. (Reuters/Xinhua)