Juncker addressed the European Parliament for perhaps the last time, as did his counterpart at the European Council, Donald Tusk, as MEPs took stock of the conclusions in a Council meeting last week in which the UK Prime Minister Boris Johnson secured tweaks to the Brexit deal, reports Efe news.
"In truth, it has pained me to spend so much of this mandate dealing with Brexit when I have thought of nothing less than how this union could do better for its citizens," the Luxembourgish politician said.
"A waste of time and a waste of energy."
"I will always regret the UK's decision to leave the European Union but at least we can look at ourselves in the eye and say that we have done all in our power that we make sure that this departure is orderly."
"It's not possible, not imaginable, that this Parliament will have ratified the agreement before Westminster will have ratified the agreement. First London, then Brussels and Strasbourg," he concluded, to applause from the chamber.
Johnson has submitted his Brexit Withdrawal Agreement Bill which the House of Commons will debated on later Tuesday.
In an extraordinary sitting on October 19, the government pulled the deal from voting at the last minute after MPs passed an amendment meaning the Commons would only support Johnson's deal once the Brexit legislation had been approved.
Having shelved the vote, Johnson sent two letters, one unsigned asking for an extension, and another one signed arguing against it.
On Monday, the government came back with a bid to hold a clean "yes/no" vote on the deal. Opposition MPs argued that they had not had time to scrutinize the deal properly.
The Speaker of the House of Commons, John Bercow, rejected the vote, saying the topic had already been debated on Saturday.
Tusk on Tuesday said the Council was watching developments in the UK closely and consulting on how to respond to the letter.
"It is obvious that the result of these consultations will very much depend on what the British parliament decides, or doesn't decide," he said. We should be ready for every scenario.
"But one thing must be clear. As I said to Prime Minister Johnson on Saturday, a no-deal Brexit will never be our decision," he added.
The UK's PM looks to win over rebel members of his party and some opposition Labour MPs with his new deal, which has replaced the Irish backstop mechanism written into the previous version by his predecessor Theresa May.
The backstop, which sought to ensure a soft border between Northern Ireland and the Republic of Ireland, hit a wall in the form of the European Research Group, a band of pro-Brexit Tories who voted against it, eventually leading to May's resignation.
( With inputs from IANS )