LONDON, Dec. 23 (Xinhua) -- Britain could be heading for a "disorderly" exit from the European Union (EU), a leading academic warned on Friday.

"If there is no organised deal by the end of the two-year period, then there will be disorderly Brexit," said Catherine Barnard, Professor of European Union Law and Jean Monnet Chair of EU Law at the University of Cambridge.

"I don't think it is in anybody's interest to have a disorderly Brexit but the government is planning for it in case it happens," Barnard told Xinhua at a press briefing for the launch of the "Brexit: Six Months On" report from the London think-tank UK in a Changing Europe.

The British Prime Minister Theresa May has committed to triggering divorce proceedings from the EU by the end of March, following a mandate given by the exit result in the June 23 referendum. This would begin a two-year countdown to a formal exit.

Barnard, a specialist in EU law, cautioned that the upcoming Brexit negotiations would be multiple and complex.

"The problem is capacity, on the UK side and also on the EU side. There are real concerns because of the sheer breadth of the issues that are to be negotiated that it may well take a whole lot longer than two years," said the professor.

According to Barnard, government ministers, including May and Brexit Secretary David Davis, had begun to talk about transitional arrangements to cover a time gap between the end of the divorce talks, likely to be April 1, 2024, and the implementation of an agreement over trade access and other issues.