Bookmakers have shortened their odds that Article 50 — the two-year notice period the must give to officially leave the EU — will never be triggered.

Sky Bet currently has 6/4 odds on Article 50 happening in "2018 or later or not at all," the favourite option in its Brexit betting market. This is even shorter than the 2/1 odds it gave the same bet in late July.

Although Prime Minister Theresa May has always insisted that "Brexit means Brexit" since she became leader of the UK, the complexity of actually leaving the EU is starting to emerge.

EU officials said on Monday that the UK should not expect a Brexit to happen before at least 2020, with one diplomat telling the Financial Times that British politicians have "to sort themselves out", saying:

"They come from London and they don’t know what they want. They don’t know what their government wants, what their parliament wants. They have not prepared."

Bureaucracy and the Law could be a problem

The clock is ticking for the EU as well as Brits. European Parliament elections are set to take place in 2019, and a brand new assembly could theoretically block any proposed Brexit terms. That means Article 50 will have to be triggered either at least two years before then to avoid an overlap or afterwards, when negotiations can be conducted with a new EU parliament.

Another potential roadblock is the UK's own House of Lords. Tory peer Baroness Patience Wheatcroft told the Times on Monday that the Westminster's Upper House could delay a Brexit taking place if it went through the Commons. "I think the Lords might actually delay things. I think there’s a majority in the Lords for remaining," she said.

On top of that, a crowdfunding scheme called #BrexitJustice that wants to use courts to prosecute pro-Brexit politicians it claims lied to the public during the referendum campaign, has cruised past its £100,000 ($133,565) target to raise £145,000 ($193,669).

The legal aspects of Brexit are still unclear as the vote was not legally binding and many have said the decision to follow through on it should go straight to the UK's Supreme Court.

Angela Merkel insists Article 50 must be triggered before Brexit talks

Here are Sky Bet's current odds on when Article 50 will be triggered:

2018 or later or not at all — 6/4

January 1 to March 31 2017 — 9/4

April 1 to June 30 2017— 3/1

July 1 to September 302017 — 7/1

October 1 to December 31 2016 — 9/1

October 1 to December 31 2017— 9/1

July 1 to September 20 2016— 33/1

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