The European Union harbours “grave suspicions” about the dominance of Google and has not ruled out breaking it up, the bloc’s competition commissioner has warned.

Margrethe Vestager told The Telegraph that the threat to split the internet giant up into smaller companies must be kept open.

In June last year, the Danish commissioner hit Google with a record £2.1 billion fine – which the firm is appealing against – for giving its own comparison shopping service an illegal advantage in search results.

Google now faces two other separate cases. Mrs Vestager admitted her officials had “grave suspicions” about the firm, which has a 91.5 per cent share of the search engine market in Europe.

“I think it important to keep that question open and on the agenda,” she said when asked if the only solution to its dominance was to break up the company.

“We are not there yet but it is important to keep an awakened eye.” She warned that the search engine could become so big as to be indispensable for businesses and the economy.