Merkel delivers Brexit ultimatum to Johnson on UK PM's first visit to Berlin

Merkel said Johnson needed to come up with specific proposals on alternatives to the so-called Irish backstop -- the divisive part of the Brexit deal that the UK government wants to abandon -- after he doubled down on a push to remove it without providing any further details.

Speaking at a joint press conference in Berlin on Wednesday evening, Johnson said that he welcomed the "blistering timetable" but said that the "onus is on us" to find a practical solution to the political deadlock.

Referencing Merkel's campaign slogan in German, Johnson said: "wir schaffen das," or "we can do it," bringing the Chancellor to chuckle along with a crowd of laughing reporters.

Johnson's trip to Germany -- the first foreign trip as British Prime Minister -- is the first leg of a European trip to attempt to make the EU shift its position on Brexit.

As he was welcomed with a military honors, a small group of demonstrators could be heard protesting with the chant, "no Brexit."

The British Prime Minister will continue his trip on Thursday in Paris with the French President Emmanuel Macron.

Johnson is pushing for the EU to ditch the so-called Irish backstop clause, the specific section of the Brexit withdrawal agreement that is designed to prevent the return of a hard border between Northern Ireland, which is part of the UK, and the Republic of Ireland, which is part of the EU.

However, his plan to woo the European leaders into renegotiating the Brexit deal looked doomed even before his plane took off.

Ahead of their Wednesday meeting, Merkel said that while the EU was ready to find a solution, "there is no need to re-open the [deal]."

"Britain needs to decide which way it goes. We have made our offer to work closely on matters involving the economy, security and foreign policy and we will see what way Great Britain chooses," the chancellor said in Reykjavik on Tuesday.

It was a clear sign that Merkel will stick to the official EU line, insisting that the deal signed by Johnson's predecessor Theresa May is the best the bloc can offer.

France also indicated there is no room for a maneuver. A spokesman for the French government told CNN that the EU's position on Brexit is unified and unchanged.

"Britain should have no doubt France, Germany and other EU countries are totally united," the spokesperson said.

Johnson sent the EU a letter outlining his position on Monday. In it, he called for the backstop provision to be scrapped. He said it was "anti-democratic and inconsistent with the country's sovereignty as a state."

However, Johnson did not suggest any alternative plan.

European Council President Donald Tusk said on Tuesday the backstop was "an insurance to avoid a hard border on the island of Ireland unless and until an alternative is found."

"Those against the backstop and not proposing realistic alternatives in fact support reestablishing a border. Even if they do not admit it," Tusk added.

A lack of a Plan B would mean the UK is more likely to crash out of the EU without a deal. This would, according to the government's own forecasts, plunge the country into economic chaos. It could also spark food, medicine and fuel shortages.

Johnson has indicated he is prepared to take the country out of the EU without an agreement. The French government spokesperson told CNN that "in view of Johnson's position on [the] Irish backstop, the baseline scenario now seems to be no-deal [Brexit]."