Brexit 'Could Take Nine Years'

The Big Ben bell tower in parliament in central London, Britain April 26, 2016. A House of Lords committee has said "Brexit" could take years. Stefan Wermuth/Reuters

Negotiations to forge a new relationship between Britain and the EU in the event of a "Brexit" could take up to nine years, a House of Lords Committee has said.

"No firm prediction can be made as to how long the negotiations on withdrawal and a new relationship would take if the UK were to vote to leave the EU," a report published Wednesday by the EU Select Committee in the upper house of the U.K. parliament concluded.

"It is clear, though, that they would take several years—trade deals between the EU and non-EU States have taken between four and nine years on average."

It added that the process of revising British domestic law to account for the absence of EU law would be very lengthy. "Domestic disentanglement from EU law would require a review of the entire corpus of EU law as it applies nationally and in the devolved nations," it said, "such a review would take years to complete."

The report also found that the decision to leave would be final , once the process was complete: "Withdrawal from the EU is final once the withdrawal agreement enters into force," it said.