Not all union members will be striking at the same time
The BBC's Newsnight has obtained what appears to be a Royal Mail document showing the company is set for a battle with union members.
The "Strategic Overview" outlines plans to fight strikes and achieve reform "with or without union engagement".
It refers to strikes as an "enabler" of its aims, saying "strikes make things worse". Royal Mail said it "did not recognise" the document.
The postal workers' union said it believed the document was genuine.
However, Royal Mail stressed the wording sent to it by the BBC did not reflect its "policy, strategy or position".
The Communication Workers Union (CWU) has announced two nationwide strikes.
It said earlier on Thursday that the 24-hour strikes will begin on 22 October. On the first day, mail centre staff and drivers will strike. The next day it will be delivery and collection staff.
Workers voted overwhelmingly last week for nationwide action, escalating a dispute which has already caused widespread disruption to postal services, in a row over pay, working conditions and reform.
The union said it had no choice but to announce a strike after the Royal Mail rejected its latest set of proposals.
Billy Hayes, general secretary of the CWU, told the BBC: "There is no question the document is genuine, what's more worrying is that Peter Mandelson seemed to know the document quite well.
"It does seem like an organised attempt to sideline the union.
"What we need is an agreement to modernise the company with the consent of the workforce.
"We want an agreement and we want to negotiate with good faith."
Royal Mail has described the strikes as "an appalling and unjustified attack on customers".
"Customers large and small have been hoping the CWU would lift the strike threats and focus on providing the service they need and want," said Royal Mail managing director Mark Higson.
"Instead the union has given them a slap in the face."
'Make or break'
Newsnight's Richard Watson says the document - a Powerpoint presentation - appears to show that this is no ordinary strike, that the clash is beginning to bear the hallmarks of epic industrial struggles of the past.
EXPECTED STRIKE DISRUPTION
22 October: Limited processing, movement and collection of mail
23 October: Limited delivery and collection of mail
Some managerial staff and contract drivers will be brought in to move mail but services will be "very limited"
Special Delivery and Royal Mail Tracked items will still be delivered on strike days
Post Office branches will be open as usual although collections will be affected
Parcelforce will operate as normal as it has its own collection, distribution and delivery network
Customers should check the Royal Mail website or call 08457 740 740 for the latest service information
Source: Royal Mail
The Royal Mail views this as make or break for modernising the service, he says, and many believe that not since the miners' strike of 1984-1985 have employer and employee dug in so deeply.
The document, dated 24 September 2009 and marked "In strictest confidence", has several chapter headings including Our Objectives, Timeline, Non Agreement and Tactics.
Under the Objectives section the document says that "through the dispute" the Royal Mail will "deliver the necessary 2009 changes with or without union engagement".
"Maintain stakeholder confidence through the difficulties caused by IA [industrial action]" and "minimise impact on customers".
However, under a sub-heading marked "enablers to achieving objectives" it calls for a "demonstration of resolve through dispute - strikes don't work".
And a "demonstration of commercial impact of dispute - strikes make things worse - the more we can demonstrate this to our people the better".
Royal Mail denial
In the Timeline section the author talks about the possibility of failure to agree a deal saying: "If un-agreed, consider programme of reducing relationship with union."
Postal workers' representatives are interpreting it as a plan to severely limit union activity, especially because the document also speaks about reducing trade union facilities - which means limiting the arrangement where union staff are permitted to carry out union business while on the payroll.
Royal Mail said it '"did not recognise" the document and responded to a request for a statement on its veracity with the following statement:
"The contents of the e-mail sent to us by Newsnight do not reflect Royal Mail's policy, strategy or position in relation to the current dispute with the CWU.
"No member of the board or the senior management team at Royal Mail has seen, or is aware of any such presentation.
"For the avoidance of any doubt Royal Mail has never had any strategy to derecognise the CWU and nor would we seek to do so."
Under a section called Tactics, the author of the document says: "Through a mix of pressures bring union to the point where doing a deal on our terms is preferable to the alternative.
"But if they refuse, we have positioned things in such a way as there is shareholder, customer and internal support for implementation of change without agreement."
The "shareholder" which the document refers to is the government.
When asked about the documents by Newsnight, Business Secretary Peter Mandelson said: "Nobody has discussed or raised any such proposition with the government, it is completely new to me. And on the basis of the management's statement, it seems to be new to them as well.
"I gather that something in the region of £20m worth of facilities and payment for union salaries comes from the Royal Mail company, so that I assume is what this so-called evidence referring to.
"But I don't believe there is any such proposal to de-recognise the union or anything like it."