
Communication Workers Union leader Billy Hayes has called on the government to intervene, and accused government ministers of "sulking" because plans to privatise Royal Mail have been thwarted by the economic downturn.
Hayes' call came as members of the CWU began another round of strike action in locations including Coventry, Nottingham, London and Northern Ireland.
But Lord Mandelson said yesterday: "Time and again in the past, the CWU has asked ministers to intervene in their disputes and their strikes to frustrate Royal Mail modernisation. I have instructed this will not happen. It is time for the union to wake up to the need for change to stop the Mail's further decline."
Hayes told BBC Radio 4's Today programme yesterday: "It seems to us that some government ministers are sulking because they haven't yet managed to privatise Royal Mail."
The CWU is preparing to ballot union members for a national walkout, threatening more disruption to mail and parcel delivery.
Rival delivery services with large van fleets, such as that operated by Home Delivery Network, are ready to step in to deliver home shopping purchases, .
The union is objecting to Royal Mail's modernisation plan, which it says is more about cuts than introducing technology. For its part Royal Mail accuses the union of walking away from an agreement both sides made in 2007 that would ensure a future for the postal delivery service.