By James Landale
Deputy political editor, BBC News
Unions are fearful over Mr Brown's plans to cut the budget deficit
Union bosses are preparing to confront Gordon Brown over public spending cuts at a rare summit at the PM's country residence, the BBC has learned.
About 15 general secretaries will attend Friday's meeting at Chequers.
It has been organised to discuss the government's plans to tackle unemployment in the coming months.
But union sources say they will also raise fears about about job losses, as the government attempts to reduce its budget deficit by cutting spending.
They also want to set out their policy agenda to the prime minister ahead of the TUC and Labour conferences and feed ideas into the party's draft manifesto for the general election.
A meeting of union leaders at Chequers is very unusual as both Mr Brown and Tony Blair have wanted to avoid raising memories of so-called "beer and sandwiches" summits of the past when the unions held sway over Labour governments.
There are no union leaders included on the official published lists of guests who have visited Chequers since Mr Brown became prime minister in 2007.
Downing Street has made no effort to publicise the three-hour-long summit which will include lunch.
A No10 source said the meeting would be "no love-in" but emphasised that the government had a good case to make that it was protecting the unions' jobs during the recession by encouraging apprenticeships and subsidised work places.
He added: "I can categorically rule out beer but can't be so firm on sandwiches."
The BBC has been told that around 15 general secretaries from the main unions - including some not affiliated to the Labour Party - will be at the meeting.
They include the likes of Brendan Barber of the TUC, Tony Woodley and Derek Simpson of Unite, Dave Prentis of Unison and Paul Kenney of the GMB.
One senior union source said the meeting was "to discuss in advance of the Labour conference issues that are of contention between unions and the party".
The source said: "We are talking to Gordon Brown and his colleagues about the potential cuts in public spending and its effect on the public sector.
"We do not want people losing their jobs during a recession. If you start throwing council workers on the dole, you are throwing away a lifeline to local communities at a time when the government is helping bankers.
"There is a move to shift the blame (for the recession) onto the public sector."
They added: "There is another route and its not about cutting jobs.
"It is about making sure that the public services you deliver are the ones you want, not chucking money into the hands of the private companies.
"Making the public sector pay for the economic crisis is the wrong route."
The source suggested that the unions wanted public spending cuts to focus more on "big ticket" items such as the Trident nuclear weapons system and ID cards, alongside higher taxes for bailed-out banks.
Another senior union source said: "Most people under-estimate how much there's going to be a drastic reshaping of the economy. The people who are going to be smashed are not those on £200,000 but the people on £20,000. There is a lot of concern among people. They are very very worried and they're the people at the bottom of the scale."