European judges dealt a hammer blow yesterday to David Cameron’s attempts to crack down on the abuse of Britain’s visa system.

Strict rules forcing foreign family members of European Union residents to get a permit before visiting the UK were scrapped by the European Court of Justice.

This leaves Britain facing a fresh surge of non-EU migrants if they are related to someone living in the EU, and encourages people who want to exploit Britain’s way of life entering the country.

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Test case: Sean McCarthy, a dual British and Irish national who lives and works in Spain, challenged the law because his Colombian wife needs a permit to visit Britain despite their children being British (all pictured)

The ruling by the court, which interprets EU law, also makes it less likely the Prime Minister will be able to renegotiate rules on freedom of movement.

Mr Cameron has pledged to end abuse by so-called ‘third country nationals’ – those from outside the EU who gain rights to live in the UK by marrying non-British EU citizens.

Ministers are concerned that sham marriages to EU citizens accompanied by easy-to-obtain residence papers in some EU countries would become another back door into Britain.

The ruling came in a case brought by Sean McCarthy, a dual British and Irish national who lives and works in Spain, and his wife, a Colombian.

They claimed her rights to freedom of movement were being infringed because she has to obtain a ‘family permit’ visa every time she wants to travel to the UK even though she holds an EU Residence Card issued in Spain and both their children are British.

Freedom of movement: The ruling is a blow to politicians' promises for tighter migration controls

THOUSANDS OF JOBS TO BE ADVERTISED ONLY IN THE UK Thousands of jobs will be advertised in the UK only after ministers agreed a new deal with Brussels. Under current rules, any jobs posted on the Government-run website Universal Jobmatch must also be placed on a European website, which helps would-be migrants search for work. EU countries have now agreed to allow firms to advertise domestic vacancies only in their own country. The deal could encourage more companies to recruit locally because they would have to specifically opt-in if they wanted to advertise outside the UK. Employment Minister Esther McVey said: ‘The new rules will significantly reduce the number of jobs advertised in Europe and put British residents first. We will continue to work to ensure the system remains fair to jobseekers and to businesses.’ The proposal still needs to be passed by the European Commission. Advertisement

Ruling in the McCarthys’ favour, the European Court said Britain was ‘not permitted’ to bar the spouse and children of an EU citizen from entering the UK without a visa.

The Government had introduced the rules because it was concerned that residence permits handed out by other EU nations did not meet international security standards. The judges said Britain was able to assess documents at the border.

The ruling only applies to the families of EU residents who are living in the EU outside their home nation. If, for instance, Mrs McCarthy was married to a Spanish man living in Spain, she would still need to apply for a visa.

Tory MEP Timothy Kirkhope, the party’s spokesman in Brussels on justice and home affairs, criticised the judgment. ‘Britain will always be best placed to deal with its own immigration needs not a judge in Luxembourg,’ he said.

Lord Green of Deddington, chairman of Migration Watch UK, said: ‘This is yet another ECJ judgment which weakens our ability to control entry to the UK. This ruling trumps a UK immigration control designed to prevent abuse.’