More than 90 per cent of Hong Kong's exports are re-exports, which are shipped to or from the mainland for processing.

Despite a lockout at US west coast ports in late September and early October, the robust growth, the fifth consecutive export gain this year, exceeded the market forecast of 9 per cent and followed a 10 per cent year-on-year increase in September.

"The disruption in the west coast of US last month has not had that great impact on the trade figures of Hong Kong... as many exporters diverted the shipments to air carriers to get around the lockout," said Erik Christensen, managing director of Modern Terminals - one of Hong Kong's largest container terminal operators.

"Some of our cargoes were delayed until November so we are seeing extraordinarily strong loading in November," he added.

"There's no reason to doubt that this performance will not be repeated in the fourth quarter, but it all depends on whether China can maintain its strong export growth," Reuters quoted Paul Tang, senior economist at Bank of East Asia, as saying.

The mainland's exports surged 31.5 per cent in October to US$31.9 billion.

SAR's domestic exports last month continued to shrink, falling by 12.6 per cent, as most of the territory's exported goods are made on the mainland.

Meanwhile, imports jumped 13.4 per cent to HK$153.4 billion (US$19.67 billion), widening the trade deficit for the month to HK$2.8 billion (US$358.97 million) from HK$1.9 billion (US$243.59 million) a year earlier.

The retained imports, which rose back distinctly last month, indicated a strong domestic consumption, a government spokesman said.

But Daniel Chan, senior economist at Dao Heng Bank, said the increase in imports may have been due to greater demand for capital goods rather than end consumer demand.