One of Ed Miliband’s closest advisers has torn into the Daily Express over its front page about millions of “hidden” migrants, saying it was offensive to suggest the British-born children of foreigners were immigrants.

Lord Wood, a shadow minister without portfolio, wrote an open letter to the newspaper’s owner, Richard Desmond, saying the clear implication is that the children of immigrants who are born and raised here are “really” immigrants too.

The article refers to statistics from Migration Watch, the organisation run by Sir Andrew Green, who is soon to be ennobled as a crossbencher, but Wood points out that there is no quote from the group to justify the headline that the supposed immigrants are “hidden”.

“I am sure that you are neither responsible for every editorial judgement made by your newspapers nor seek to interfere in headlines like some other proprietors,” Wood wrote in his letter, which was published by the Huffington Post.

“But can I ask you this: are you happy that the Daily Express is saying that we should consider people such as Prince Charles, Ed Miliband, Boris Johnson and Winston Churchill as migrants ‘hidden’ from the British public by official statistics? And is it correct that the Daily Express is suggesting that the children of Nick Clegg and, for that matter, Nigel Farage are ‘hidden migrants’?”

Wood wrote that he found the insinuation “offensive as someone who is British, proud of my country, and with a German mother who has lived in Britain permanently and happily for over 50 years”.

“I also find it curious that a paper owned by someone whose maternal grandparents came to this country from Ukraine in search of a better life would be happy to give this impression about the descendants of immigrants,” he wrote.

“Your paper has long argued that members of the British public have legitimate concerns about the impact of immigration - a position shared by the Labour party and Ed Miliband. But suggesting by implication that people who are born and brought up here are somehow un-British or foreign because one or both of their parents emigrated here from abroad surely is not legitimate, but rather is inaccurate and, to many, highly offensive.”

The letter marks Labour’s latest battle with the right-leaning press, after Miliband took the Daily Mail to task over its article that claimed his late father, a Marxist academic, was a “man who hated Britain”. The Labour leader has also risked annoying Rupert Murdoch’s Sun title after he posed with a copy of its World Cup issue and then apologised for doing so, after an outcry because it coincided with the phone-hacking trial and Hillsborough inquest.

Express Newspapers have not yet responded to a request for comment.