A survey has shown that business activity in the euro zone slowed to a 31-month low in January amid growing signs of economic weakness.

An NTC Research survey of business leaders fell to 52.7 points in January, down from 53.3 in December. The result was marginally below economists' forecasts for 52.8 and was still above the 50-point level that indicates expansion.

NTC said the decline was driven by weakness in the service sector where the output index dropped to 52 in January from 53.1 in December while the manufacturing index picked up to 53.9 from 53.5.

Economists said the overall decline added to the growing body of evidence that the euro zone economy was weakening, adding pressure on the European Central Bank to ease its interest rates despite record inflation.

Meanwhile, official figures show that factories in the euro zone saw demand surge faster than economists  expected in November due to booming transport equipment orders.

New industrial orders in the euro zone rose 2.7% in November from October and jumped 11.9% over the same month last year, the EU's Eurostat agency said.

This marked a sharp improvement from October when orders rose 2.5% over the month.

November's data showed that the overall increase was driven by  strong demand for volatile transport equipment, with new orders up 7.3% in the month and 28.7% over the year.