London is in the throes of a 1980s revival. In Westminster, Tory politicians loudly extol the economic and moral virtues of privatisation, while City bankers hum the Pet Shop Boys' Let's Make Lots of Money and unions dust off their anti-capitalist drums.

Sadly the 1980s retrospective does not signal a return to the 5 per cent annual growth of the boom years; the driver is the imminent flotation of the Royal Mail.

While the Irish Government has high-quality family silver still to hock, the UK cleared its cupboards in the 1980s and the postal service is more like a forgotten spoon with the family crest than a grand teapot.

When the Royal Mail, whose origins date back to Henry VIII, begins to trade on the London Stock Exchange on Friday it will be fourth-time lucky for the British government, which has been trying to sell the company for decades.The much-
maligned company has for years provided tabloid newspapers with stock stories about lost Christmas cards, strike threats and "Sorry We Missed You" cards dropped to customers who never left their homes.

Shorn of its huge pension deficit and restructured to serve e-tailers’ growing need for package deliveries, the Royal Mail now looks like an attractive prospect.

Even so, the government seems to have been taken by surprise at the popularity of the offering, which is heavily oversubscribed and is expected to list at the top of its £3 to £3.30 a share band.

Fanning those flames is City stockbroker Panmure Gordon, whose analysts said in a note earlier this week that the company could be worth as much as £4.5 billion (€5.3 billion), significantly more than the £3.3 billion valuation the government and its advisers Barclays, Bank of America Merrill Lynch and Goldman Sachs are selling shares at.

Rising Labour star and shadow business secretary Chuka Umunna has picked up that forecast and run with it, urging the coalition government to pull the plug on the privatisation. Not only is the Royal Mail's business itself undervalued, argues Umunna, but the company's real estate assets are significantly underpriced at £787 million, with the Mount Pleasant sorting office in fashionable Clerkenwell alone worth £1 billion.

The Royal Mail’s unions have taken up Labour’s calls and are threatening to strike if the privatisation goes ahead, although their stance has not prevented 149,632 of the Royal Mail’s 150,000 staff from taking up a free-share sweetener which, if the initial public offering goes ahead, will be wo- rth about £2,000 per worker.

On the other side of the fence is the government, with Liberal Democrat business secretary Vince Cable accusing Labour of acting irresponsibly and reminding potential investors that shares can go up as well as down.

“Equity investment always involves risk, particularly when the company in question is new to the market. In the light of this it is dangerous to imply that there is an easy bargain,” he wrote to Umunna on Monday.

Over at the Conservative Party central office, it is win-win for a party gearing up for an election in less than two years. Minister for business and enterprise Michael Fallon has promised small investors equal access to the issue and about 30 per cent of the float has been set aside for the retail market.

If Royal Mail’s shares rise when it begins to trade conditionally on Friday, the Tories will have delivered for small shareholders – some of their key supporters – and given a feel-good boost to the economy. In the unlikely event that the shares fall in maiden trading, the Tories will have demonstrated they can handle state sell-offs commercially, which, with the more challenging disposals of Britain’s banks yet to come, is no bad thing.

Yesterday the business select committee, an influential parliamentary body that has held private equity to account and savaged the bankers, called a last-minute hearing into the Royal Mail sale. Cable will appear before it today to answer questions about pricing and the controversial employee share scheme. Union activists are planning to stage a protest outside the hearing, dressed up as highway robbers. But don’t expect any last-minute deviations from the IPO plan: the answer is already in the post.