The Brexit vote may send the European Union "down the drain" according to the German vice chancellor.

Angela Merkel's second in command has warned that the EU could collapse if Brexit negotiations are not well managed.

Sigmar Gabriel said Britain can not keep the 'nice things' about Europe without taking any responsibility.

"Brexit is bad but it won't hurt us as much economically as some fear - it's more of a psychological problem and it's a huge problem politically," he added.

It comes as British Prime Minister Theresa May prepares to meet her ministers on Wednesday to discuss their priorities for the Brexit negotiations.

Virginia Mayo / AP

He also publically declared that the proposed Transatlantic Trade and Investment Partnership (TTIP) is now dead in the water.

"Negotiations with the United States have de facto failed, because we, as Europeans, must not bow to American demands," he told the German media.

US president Barrack Obama previously stated that if the deal is not completed now it will be years before a trade deal can be negotiated, given a schedule of elections in the US and across Europe.

Throughout the negotiating process, a protest movement against the liberalisation of trade between the US and the EU formed.

One of the main concerns is that the deal would give companies legal rights that are more powerful than those of individual states due to TTIP's investor-state dispute settlement' (IDIS) mechanism.

This allows businesses to take legal action against governments who act in ways which compromise the trade agreement and lead to smaller profits for businesses.