Three leading German business groups on Monday issued an appeal to Britain to set out its exact plans for its economic relations with the European Union after it leaves the bloc on March 29, 2019.

In a joint statement, the heads of the organizations said they were worried that even the "transition phase" after Brexit was not assured.

June summit

Dieter Kempf, who heads the Federation of German Industries (BDI), said that this phase would be made possible only if there were agreement on the future and the conditions of Britain's exit, adding that the EU and the UK needed to make progress at a summit at the end of June.

"German industry expects a binding and clear response to the proposals of the EU27 regarding the future economic relationship. London should recognize in its own interest that we Europeans can either be successful in the world together — or sink into insignificance if divided," Kempf said.

"Our companies must have clarity by October for [Britain's] plans after Brexit day," he added.

Read more: 'Armageddon' Brexit: 'No deal' scenario could hit fuel and food

Call for 'fair partnership'

The head of the Confederation of German Employers' Associations (BDA), Ingo Kramer, said that after Brexit, German companies had to be able to send their employees to their branches in the UK in just as an "uncomplicated" a way as British companies could to the EU.

"We expect by the summit in June that the Britons set up their national regulations in this regard just as generously as the EU — that would be a fair partnership," he said, adding that social welfare systems also had to be coordinated so that German workers did not pay double contributions.

Read more: Brexit causes record number of Britons to be granted German citizenship

Bavarian concerns

Alfred Gaffal of the Association of Bavarian Industry (vbw), in his turn, called for "more tempo" in the Brexit negotiations, with the main aim of agreeing a comprehensive trade deal between the EU and Great Britain.

He said Bavarian exports to Britain, which made up 7.3 percent of the southern German state's export volume, had dropped by 6.6 percent in 2017 compared with 2016 as a direct result of uncertainty over Brexit.

The three organizations have now published guidelines for German companies to prepare them for the economic consequences of Brexit.

Read more: Brexit Diaries 35: Theresa May begs for the UK's trust

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