European Union regulators plan to open a year-long extensive investigation into e-commerce as part of efforts to do away with barriers and boost cross-border trade in the bloc, the EU's antitrust chief said on Thursday.

European Competition Commissioner Margrethe Vestager said she decided to launch a sector inquiry into e-commerce trade because a number of barriers were hampering the growth of online sales as well as signs that some companies may be deliberating blocking such trade.

"It is high time to remove remaining barriers to e-commerce, which is a vital part of a true Digital Single Market in Europe," Vestager told reporters. She will put forward her proposal to the Commission in the coming weeks, with the inquiry scheduled to end in mid-2016.