LONDON (AFP) - British Foreign Secretary David Miliband said Wednesday the Labour Party must start offering "real change", in comments seen as a strong hint he may challenge Prime Minister Gordon Brown for the top job. Miliband used an article in the Guardian newspaper to say that the party, in power since 1997, could still win the next general election despite a growing threat from the main Opposition Conservatives led by David Cameron. Labour had to offer "real change, not just in policy but in the way we do politics", he said, in a piece that pointedly failed to mention Brown, who faces rising discontent from lawmakers amid a string of poor by-election results. "Let's stop feeling sorry for ourselves, enjoy a break and then find the confidence to make our case afresh," Miliband wrote. Miliband, 43, was seen as a potential challenger to Brown when Tony Blair stepped down last year but did not mount a campaign, meaning Brown became Labour leader and prime minister unopposed. Miliband's remarks have provoked a frenzy of comment in the British media, where some commentators are predicting that Brown could only have a matter of months left in office. The Daily Mail wrote in an editorial that Miliband's comments "suggest an overweening ambition." The Times, meanwhile, said the article "fires the first salvo in a deliberate challenge to Mr Brown... (and) outlines a blueprint for defeating David Cameron without mentioning the prime minister once by name." The latter two newspapers, citing unnamed sources, both reported that Brown's Downing Street office had known about the article beforehand and was relaxed about its content. Already Tuesday, Labour's deputy leader Harriet Harman, insisted in a public statement that she was not "preparing the ground for a leadership election" following Press reports that she was interested in a bid to become premier. That statement followed Press speculation about her interest in the role. Harman has been filling in for Brown in Downing Street while he has been on holiday. EU trade commissioner Peter Mandelson, a former Cabinet minister under Blair, told BBC radio Wednesday that Labour was "in flux." Last week, Labour lost the Glasgow East by-election in its central Scotland heartland, conceding a majority of more than 13,000 votes, in its third by-election defeat in as many months. Two separate opinion polls published earlier this week by The Times and The Daily Telegraph put Labour 16 points and 19 points behind the opposition. The Telegraph poll showed 74 percent of voters are dissatisfied with the prime minister himself.