A waiter sets a table at a restaurant in Seville, southern Spain June 9, 2016. Picture taken June 9, 2016. REUTERS/Marcelo del Pozo

MADRID, Dec 3 (Reuters) - Spain's service sector expanded robustly in November led by domestic demand, albeit at a slightly slower pace than in the previous month due to a decline in international trade, a survey showed on Wednesday.

The seasonally-adjusted HCOB Spain Services PMI Business Activity Index clocked 55.6 last month, down from 56.6 in October, still indicating a marked increase in activity above the 50.0 threshold that separates growth from contraction.

This marks the 27th consecutive month of expansion for Spain.

"Spain's economy remains robust, and GDP is likely to grow strongly in the fourth quarter," said Jonas Feldhusen, junior economist at Hamburg Commercial Bank. "Order book developments in the services sector remain healthy, though momentum has eased slightly."

While domestic demand remained strong, international sales fell for the first time in five months, marking the steepest decline since the start of 2024.

The private sector continued to expand at a solid pace in November, with services outperforming manufacturing.

Despite the slowdown in international trade, service providers remained optimistic about the future, with confidence levels unchanged from October. This positive outlook encouraged firms to hire more staff, although the rate of employment growth eased slightly.

A sister survey released earlier this week showed the manufacturing sector's growth slowed to 51.5 in November.

The Spanish economy is set to far outperform its peers in the euro zone in 2025 thanks to a tourism boom, a strong labour market helped by immigration, and domestic consumption. The government last month raised its full-year growth forecast to 2.9%.

(Reporting by Andrei Khalip; Editing by Joe Bavier)