David Cameron, UK prime minister © Getty

More than 1m Britons living in Europe for more than 15 years will not be given the right to vote in the forthcoming EU referendum, the UK High Court has ruled.

A group of British citizens had brought a legal challenge against the government, claiming they had been wrongly disenfranchised.

The case is significant because there are between 1m and 2m Britons living in Europe. Most of them have lived outside the UK for more than 15 years, the cut-off point for voting. No one including the UK government knows the exact number in this category.

Giving the court’s ruling Lord Justice Lloyd Jones said the government’s decision on voting complied with EU law. He added that including them would present the government with practical difficulties.

“Furthermore we consider that there would be significant practical difficulties about adopting, especially for this referendum, a new electoral register that includes non-resident British citizens whose last residence in the United Kingdom was more than 15 years ago,” he said.

He noted that electoral registration officers had “no straightforward means of checking the previous residence status of British citizens who have been resident overseas for longer than 15 years”.

The government had resisted the legal challenge. It said in a hearing this month that if the challenge succeeded, it could call into question its ability to hold the referendum by the scheduled date of June 23.

It also said complex technical changes would be needed to the online voting registration service and election management systems.

In the court hearing, Aidan O’Neill QC, representing the individuals bringing the legal challenge, said his clients “were not expats” but were Britons in Europe who wanted to vote and were using their EU freedom of movement rights to live and work in Europe.

“It’s not they have left or given up on the UK but every day of their daily lives they are relying on the fact of their British citizenship and membership of the UK in the EU,” Mr O’Neill told the court.

The current rules prevent them from participating in a democratic process, the result of which might bring to an end the EU rights on which they rely and base their working lives, he told the court.

Richard Stein, a lawyer from Leigh Day representing the claimants, said his clients would fight on.

He said: “We are obviously disappointed that the High Court has denied us the opportunity to challenge the decision by the government to exclude British citizens from the EU referendum.

“We now intend to take the legal battle to the Supreme Court, the highest Court in the country, so that all British citizens living elsewhere in the EU can be part of the democratic process to vote in this referendum which will have a very real impact on their lives,” he said.

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