BRUSSELS, Oct. 21 (Xinhua) -- European Council President Charles Michel on Wednesday called on the United Kingdom (UK) to decide once and for all whether it wanted to reach a deal on its future relationship with the European Union (EU) after its withdrawal from the bloc.

"You can't have your cake and eat it too," Michel said when addressing the European Parliament about the outcome of the EU summit last week, which focused on the ongoing EU-UK negotiation.

He said the UK had an important choice to make about its own future. "It's not about choosing a negotiating tactic. It's about choosing the model of society and the model of economy for their own future."

"Do our British friends want to regulate state aid? And do they want to maintain high standards in health, food security and climate, in close relationship with Europe? If so, why not commit to them in our future agreement?" Michel questioned.

"In June 2016, the United Kingdom took a democratic decision to leave the European Union. We respected this sovereign decision... But the UK wants access to our Single Market, while at the same time, being able to diverge from our standards and regulations, when it suits them," he lamented.

Stressing that "time is very short," the EU chief said the bloc stands ready to negotiate 24/7 on all subjects, based on legal texts.

Michel said the EU and the UK had still not found agreement on three "extremely difficult issues": the level playing field, governance and fisheries.

UK Prime Minister Boris Johnson had set Oct. 15 as the deadline for an agreement to be reached, but the EU's chief negotiator Michel Barnier said his team was ready to step up their work in the new round scheduled for this week.

Barnier tweeted on Wednesday that "an agreement is possible if we are both ready to work constructively & in a spirit of compromise over the next days, on the basis of legal texts."

Barnier's message was echoed by European Commission President Ursula von der Leyen, who tweeted: "Hard work needed, no time to lose."