Euro zone retail sales grew by less than expected in January, Eurostat data showed on Friday, pulled down by weaker sales of fuel and muted spending on food and online, as inflation rose above 5% and curbed consumers' purchasing power.

The European Union's statistics office Eurostat said retail sales in the 19 countries sharing the euro rose 0.2% month-on-month for a 7.8% year-on-year increase.

Economists polled by Reuters had expected a 1.3% monthly rise and a 9.1% annual gain.

Sales of food were flat in January compared to December, while automotive fuel sales fell 1.3%, reining in the overall monthly index.

Compared with January 2021, the value of sales of petrol were still 12.7% higher, but online sales were down 6.7% and sales of food, drinks and tobacco were 1.7% lower.

As a proxy for consumer demand, the sales data showed large differences across euro zone countries. Sales in Slovenia surged 32.3% year-on-year in January, while in Finland they fell 2.4%. In Belgium, sales were up a miniscule 0.3% year-on-year, while in its neighbour Germany, the euro zone's biggest economy, they jumped by 10.3%.

(Reporting by Jan Strupczewski; editing by Philip Blenkinsop)