Michel Barnier, the European Commission’s Brexit negotiator | Emmanuel Dunand/AFP via Getty Images | Emmanuel Dunand/AFP via Getty Images Michel Barnier: UK will have 18 months to negotiate Brexit deal EU is ‘ready’ to receive the Article 50 notification, Commission’s chief negotiator says.

Britain will have just 18 months to negotiate its exit from the European Union, to give the EU institutions enough time to ratify the agreement before March 2019, Michel Barnier, the European Commission’s Brexit negotiator, said Tuesday.

"Time will be short. It is clear that the period of actual negotiations will be shorter than two years," Barnier said in his first press conference since being appointed by Commission President Jean-Claude Juncker in July.

He said that if British Prime Minister Theresa May triggers the Article 50 divorce procedure by March 2017, as she has indicated, the negotiations could start “a few weeks later" but would need to be wrapped up by October 2018.

The former French minister, who spoke in both English and French during the press statement, also warned the U.K. that any deal it secures will have to be inferior to EU membership.

Barnier did suggest there could be a "short transitional arrangement" to cover the period between the U.K.'s exit and the start of any new agreement. But he added that “as long as we don’t know what the demands are, what the U.K. is ready to accept, it is difficult to talk about a transitional agreement.”

He said a small team of 30 people "with solid expertise in all policy areas" was working on the process but said the work would be “legally complex” and “politically sensitive” as “we are entering into uncharted waters.”

He also repeated several oft-repeated EU lines on Brexit, that there could be "no negotiations with notification" and that the bloc’s single market and four fundamental freedoms — including free movement of people — were “indivisible. There can be no cherry-picking.”

“Keep calm and negotiate,” he said, adding that the EU is "ready" to receive the Article 50 notification.

Barnier said he had visited 18 European countries, including Germany, Portugal, France and Greece, since being given the job. According to an EU official, Barnier's European tour was “to consult leaders and agree on a common position.”

Last week, Barnier held talks with officials from the European Parliament and European Council on the "technical and financial aspects of Brexit.” According to a Parliament official, Barnier told senior MEPs “this can’t be about revenge.”