President of the European Commission Jean-Claude Juncker listens at a news conference during the European Union Tallinn Digital Summit in Tallinn, Estonia, September 29, 2017. REUTERS/Ints Kalnins

TALLINN (Reuters) - The European Commission will propose new rules next year to ensure that the online sector pays its fair share of taxes, its president Jean-Claude Juncker said on Friday.

Critics say online firms such as Google GOOGL.O or Facebook FB.O pay too little tax in the EU by routing profits to low-rate countries such as Luxembourg or Ireland. The EU has threatened to move ahead alone rather than wait for the world's rich nations to find an accord.

“We are of the opinion that in the digital sector, tax has to be paid where it is due, be it online or be it offline,” Juncker told a news conference after a summit of EU leaders in Estonia.

“The Commission will propose next year new rules on fair and effective taxation that provides legal certainty and a level playing field for all,” he added.

Not all EU countries agree on how the digital sector should be taxed, but Juncker said he believed they would reach a deal.