A member of the Government has resigned over its plans for Royal Mail.
Labour MP Jim McGovern has quit as parliamentary private secretary to business minister Pat McFadden.
The Dundee West MP said: "I believe a PPS has to be fully supportive of proposals of the department which they serve.
"In this case, I do not support what looks to me like partial privatisation of the Royal Mail.
"In his statement Pat McFadden said he welcomed an expression of interest from the Dutch postal company TNT.
"For me, it simply beggars belief that we would employ the services of a company from abroad to tell the Royal Mail in this country where they are going wrong."
Mr McGovern told Sky News: "I believe that the Labour party manifesto in 2005, that I was elected on, committed the Government to a wholly publicly owned Royal Mail. I believe the solution to the problem should come from the British Government, our Government.
The welcome for these New Labour plans from Old Labour MPs was about as friendly as the greeting a cheery postie gets from the teeth of a snarling pitbull.
Jon Craig, Boulton & Co.
"The ultimate ownership, majority ownership, might be with the state but there will certainly be an element of privatisation"
Sky's political correspondent Joey Jones said: "We knew there was a potential rebellion on the Labour backbenches because when the plans were discussed in the House of Commons and the House of Lords, there were rebels getting to their feet to say how unhappy they were at the suggestion that part of the Royal Mail could be sold off to a private company."
The Government wants to inject private capital into the postal service following the publication of a long-awaited report into its future which called for "radical" action.