Jean-Claude Juncker said no real progress can be made until the UK submits formal written proposals and that the threat of a no-deal Brexit remains very real.
The European Commission president told the European Parliament today that despite friendly, constructive and in part positive talks with the PM this week, he has yet to offer any formal alternative to Theresa Mays deal.
The main stumbling block is Mr Johnsons insistence on scrapping the Irish backstop, the contingency plan aimed at preventing a hard border between Ireland and Northern Ireland.
Mr Juncker told MEPs in Brussels: I said to Prime Minister Johnson that I have no emotional attachment to the safety net, to the backstop, but I stated that I stand by the objectives that it is designed to achieve.
That is why I called on the Prime Minister to come forward with operational proposals, in writing, for practical steps which would allow us to achieve those objectives.
Until such time as those proposals have been presented I will not be able to tell you, looking you straight in the eye, that any real progress has been achieved.
He also said he will not seek an extension to the 31 October deadline despite MPs in the UK passing a law aimed at forcing the PM to delay if no deal is in place by 19 October.
Mr Juncker said the EU is prepared to work day in, day out, morning until night on efforts to reach an agreement but said: I am not sure that we will get there.
EU chief negotiator Michel Barnier told Mr Johnson it is not enough to keep repeating that he does not like the backstop without producing any proposals to replace it.
He said major problems like the future of citizens hit by Brexit, peace in Northern Ireland and the protection of the EUs single market and the Irish economy have not yet been addressed.
Mr Barnier told EU lawmakers: We need legally operative solutions in the withdrawal agreement to respond precisely to each problem – to address each risk – that Brexit creates.
Some three years after the British referendum, its not a question of pretending to negotiate.
Its our responsibility to continue this process with determination and sincerity.