"It is time to face up to the hard facts".
Many saw the speech as a clarification of London's position on the future EU-Britain relationship, but Juncker's Wednesday statements indicate that speeches will not take the place of signed agreements.
"There was this Mansion House speech by Mrs".
He said: 'Mrs May, we did not vote for a transition period, we voted to leave this organisation, we voted to leave the customs union, we voted to leave the single market.
European Commission president told MEPs he needed "specific proposals" from the UK.
"The draft protocol on Ireland should not come as a surprise or a shock it translates last December's agreement into a legal text", Juncker said.
London's response to the guidelines was cold in turn, with British Chancellor of the Exchequer Philip Hammond calling them "very tough" on Wednesday, claiming that Britain would refuse any final trade agreement that did not include financial services.
The European Union's chief Brexit negotiator warned Britain Tuesday against undercutting EU rules and regulations that underpin anything from social protections to food security when it leaves the bloc.
The European Parliament's Brexit co-ordinator Guy Verhofstadt also called for more details from Ms May.
The EU "will stand firm and united when it comes to Ireland", Juncker said at the start of the Brexit debate.
"We will keep making this point in the run-up to the European Council next week", Juncker told the European Parliament."We are expecting more clarity on the American side in the coming days and will continue to work with our partners to push for an exemption". If you chose to jettison, leave behind, the common agreements and rules then you have to accept that things can not remain what they are ...
"One can not have at the same time the status of a third country and demand at the same time the advantages of the (European) Union", Barnier told a plenary session of the European Parliament in Strasbourg.
The UK will "regret" its decision to leave the European Union, Brussels' top official has warned.
That comment elicited repeated shouts of "It's a British issue sir", from UKIP member David Coburn.
Mr Farage, an ally of U.S. president Donald Trump, said the United Kingdom should leave the European Union without a transition deal and claimed a transatlantic trade deal could be struck "in 48 hours".