Thousands of child refugees could bring their relatives to live with them in Britain after a judge ruled that keeping families apart breached their human rights.

Strict Home Office requirements have previously meant only adults who have fled to the UK can apply for relations to join them here.

But the country’s top immigration judge has overturned the rules for the first time by allowing a teenage Eritrean refugee to be reunited with his mother and younger brother, who are still in East Africa.

Last night, there were warnings the ruling could lead to thousands more youngsters applying for relatives overseas to join them in the UK on human rights grounds – and put more children at risk of being sent here by people-smuggling gangs.

Strict Home Office requirements have previously meant only adults who have fled to the UK can apply for relations to join them here (pictured a refugee family at a makeshift refugee camp at the Greek-Macedonian border)

More than 4,000 unaccompanied children are already in the care of UK councils having fled conflicts in the Middle East and Africa.

Last month, the Government agreed to take in 3,000 more in refugee camps across Europe, each of whom will cost £50,000 to resettle.

In the light of the new court case, Ministers are rewriting the rules to allow judges more ‘discretion’ in letting relatives into Britain.

Lord Green of Deddington, chairman of Migration Watch, said last night: ‘This case is a matter of concern.

‘The public interest in effective immigration control must be given weight in cases of this kind. Human rights considerations are important but cannot be given free rein.’

MP Peter Bone, a former chairman of a parliamentary group on people-trafficking, said: ‘I think the Government will be very alarmed by this ruling. It will expose young children to awful risks, because traffickers will say to families, “Let us have your son, we’ll get him into Britain then you can all come.”'

The new case was won by a teenage boy known only as ‘M’, who arrived in Britain by himself aged 16 in 2012, having fled his native Eritrea where his father had been ‘imprisoned for political reasons’.

After being initially refused asylum, he was given leave to remain as a refugee until 2018, legal papers show. His mother and younger brother, then living in Khartoum, Sudan, applied for visas to join him, but were refused entry to Britain.

HOME OFFICE BANNED ENTRY TO BRITAIN Only dependent partners and children of refugees should be admitted into Britain, according to Home Office rules on family reunion. ...BUT JUDGE OVERRULED The judge, Mr Justice Bernard McCloskey, said the right to a family life overrode migration controls – as did the fear that the teenager might make the ‘precarious journey’ back to Africa to rejoin his relatives if denied entry into Britain. Justice Bernard McCloskey (pictured) made revolutionary ruling by allowing a teenage Eritrean refugee to be reunited with his mother and younger brother, who are still in East Africa Advertisement

However, supported by the Joint Council for the Welfare of Immigrants (JCWI), the Eritreans appealed against the decision under Article 8 of the European Convention on Human Rights, which guarantees the right to a family life.

Ruling the family could come to the UK, Mr Justice Bernard McCloskey, President of the Upper Tribunal (Immigration and Asylum Chamber) said M was ‘under-achieving as a person’ without his loved ones and ‘society’ would be better off if they are together again.

The teenager might also try to make the ‘precarious journey’ to rejoin them in Sudan if they are kept apart, he predicted, which would also go against his human rights.

A JCWI spokesman said: ‘This doesn’t mean child refugees will always be able to reunite with family abroad, but it does provide a ray of hope for families in the future.’