By Nicola Boden
Last updated at 2:41 PM on 30th March 2011
In the Commons, there has been little evidence of a thawing in relations between the Miliband brothers.
And away from politics, their relationship appears to remain just as strained.
Labour leader Ed today announced he will marry his long-term partner in May - but his brother David will not be his best man.
Engaged: Ed Miliband and partner Justine Thornton today
Mr Miliband says it is the 'right time' for the couple to tie the knot
The younger Miliband, who performed the role at David's wedding 13 years ago, says he has decided against having a best man for the ceremony on May 27.
The move came after speculation that he was struggling to decide whether to ask David to take part because of ongoing tensions in the wake of the leadership contest.
Ed pulled off one of the biggest upsets in modern political history to beat his older brother to the top job, thanks to greater support from the unions.
Friends of the Labour leader had suggested he risked being humiliated if he asked his brother to be best man and was turned down.
But there were also fears that if David accepted, he could poke fun at the groom as is customary in the best man's speech.
Ed, 41, speaking outside his home today, insisted David was 'delighted' at the news and that he had been the first person he called after his mother.
Tensions: The Miliband brothers at the Labour party conference last year
Beaming: A happy Ed Miliband in the Commons during PMQs today
The younger Miliband had been under pressure to marry Justine, a barrister and the mother of his two young sons, since winning the leadership last autumn.
In doing so, he became the first leader of a major political party to live with his family out of wedlock.
MARRIAGE LEVELS FALL
Marriage levels have fallen to their lowest level since 1895, according to new figures.
The provisional number registered in England and Wales in 2009 was 231,490.
Across the UK, the provisional level is 266,950 - almost half the peak figure of 480,285 in 1972.
In Scotland, levels are down 4.8 per cent on 2008 and 6.8 per cent lower in Northern Ireland.
For England and Wales, the number of unmarried adults rose producing the lowest marriage rates since they were first calculated in 1962.
The provisional marriage rate for men aged 16 and over was 21.3 per 1,000, down from 22 in 2008. For women, it was 19.2 - down from 19.9.
His family set-up also came under scrutiny when it emerged his name was not on the birth certificate of his eldest son, Daniel.
The leader claimed he had been so busy he forgot. The couple had a second son, Samuel, in November.
Ed had previously insisted he was 'too busy' to get married but now says it is the 'right time' for the couple to tie the knot.
They are to have a 'small ceremony' at Langar Hall hotel near Nottingham, close to where Miss Thornton grew up and a favourite with designer Paul Smith and Cliff Richard.
His brother David and his wife Louise will be among around 50 guests at the wedding and Ed said there might be a 'low key' stag night beforehand.
They will then have a larger party in Doncaster, his constituency, after returning from honeymoon.
A daytime wedding for around 50 people at the hotel, which also hosted the marriages of actress Sarah Lancashire and footballer Michael Dawson, will cost the couple around 5,000.
Langar's regular wedding planner Pascal Bouyssounouse - dubbed Mr Cupid - will be taking charge.
'This is going to be a fantastic day for us both and I feel incredibly privileged to be marrying someone so beautiful and who is such a special person,' Ed said.
'It's the right time for us to do this and I'm really looking forward to a lovely day. We're going to have a party in Doncaster when we get back from honeymoon - which will be in an undisclosed location.
'At the end of the day we're in our 40s and we've got two kids - so it wasn't a case of me suddenly popping the question. This is just something we think is right for us.'
Team: Ed Miliband and Justine before his conference speech last year
Young family: The couple with their second son Samuel last November
His wife-to-be, an environmental lawyer, added: 'Ed wasn't even an MP when I met him and at the end of the day I am marrying him because of who he is and not because of what he's doing now.
'We're planning on a small ceremony, all at the hotel with everything at the same place and we're looking forward to it very much.'
David Cameron offered his congratulations when he faced the Opposition leader across the Commons chamber at question time.
'On behalf of everyone in the House I can congratulate you and Justine on the happy news of your forthcoming wedding and, I am sure with everyone, to wish you a long and happy life together,' the Prime Minister said.
Unable to resist a dig at his adversary, he added: 'When I was leader of the opposition, I would have done anything to have a honeymoon. He probably feels the same way.'
Mr Miliband was teased about his marital status in an interview with Piers Morgan earlier this year and insisted he would only marry at the right time for him.
'The more people who challenge me on it from a political standpoint, the more resistant I will become,' he said.
'We'll get married because we want to get married and love each other very much, no other reason.
'Marriage is a good institution and part of having stable families, but there are also people in unmarried relationships with stable families. I don't think politicians should order people to get married.'
Langar Hall hotel near Nottingham where the couple will marry on May 27
The entrance to the boutique hotel, which is near where Miss Thornton grew up
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