THE family of David Miliband, the foreign secretary, was branded untrustworthy and misleading by Home Office and Foreign Office officials when it tried to migrate to Britain, documents to be released tomorrow will reveal.

The foreign secretary will find his department thought that his father and grandfather played fast and loose with the truth and lied to immigration officers.

The government papers accuse Miliband’s late grandfather, Samuel, a Polish migrant, of exaggerating the antisemitism he faced in Belgium after the second world war in order to move to Britain. A hand-written Home Office report from March 8, 1949, doubts the Milibands’ honesty, stating: “Mili-band, father and son, have so misrepresented the case in the past, I am afraid we can place no reliance on their statements.”

Samuel’s claim that he faced “Nazi” style antisemitism were dismissed as “very thin”. His son Ralph (the foreign secretary’s father) was accused by the Home Office of making repeated “misrepresentations” to support Samuel’s application.

The files also reveal that when embassy officials interviewed Samuel directly he admitted the claims of Nazi-style persecution were untrue and that he was not being expelled from Belgium.

The revelation of the way in which the foreign secretary’s forebears talked their way into Britain is particularly piquant given Labour’s record on migration. When David Miliband took up the post last year, he said immigration would remain a key issue. Since then, however, Labour has continued to preside over record levels of immigration despite concern among voters that the rate is too high.

The documents, obtained by The Sunday Times under a freedom of information request, reveal how a struggle over migration played a key part in the fortunes of the Miliband family.

When the Germans overran Belgium in May 1940, Samuel and Ralph fled because they were Jews. They were given refuge in Britain. Ralph stayed and later became an influential Marxist academic and close friends with Tony Benn and other Labour grandees until his death in 1994.

Samuel returned to Belgium in 1946. Finding his business destroyed and refused a work permit, he tried to return to Britain. Between 1948 and 1954 he applied nine times to be made a British citizen or to have six-month visas extended.

The documents, which include reports from Special Branch, show that immigration officials recorded Samuel had “misrepresented the case” when he claimed there was growing antisemitism in Belgium.

They also cast doubt on his claims that he needed to visit his son Ralph in England because the young academic was suffering “nervous depression”.

A letter sent on behalf of Ernest Bevin, then foreign secretary, in May 1948 stated: “Mr Miliband was interviewed by a representative of His Majesty’s embassy and stated there had never been any question of his expulsion from Belgium.

“The suggestion the Belgian authorities are adopting a ‘Nazi’ or antisemitic policy . . . seems to be without foundation.”

After the war, hundreds of thousands of Jewish people were left homeless and stateless and millions of people were beginning to understand the enormity of the Holocaust. In 1948, however, Belgium was under the relatively liberal rule of Paul-Henri Spaak, the Socialist.

Martin Conway, a historian at Balliol College, Oxford, said there was almost no evidence of government or police persecution of Jews in Brussels after the war. “It could not be said they were forced out of Belgium because of antisemitism,” he said.

Harold Laski, the eminent intellectual, came to the aid of the Milibands. In personal correspondence with James Chuter Ede, then home secretary, Laski asked him “as one socialist to another” to allow Samuel residency to show the world that the West was more compassionate than “the Russian way”. In the end Samuel’s application was successful.

Yesterday David Miliband and his brother Ed, the Cabinet Office minister, declined to comment. The Foreign Office said: “This is a personal matter for the foreign secretary.”

The documents have echoes of the position Michael Howard found himself in when he was Tory leader. While his party was opposed to mass immigration, Howard was forced to admit that his father had lied about his circumstances when he applied for British citizenship in 1947.

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