The Cabinet Secretary, Sir Gus O'Donnell (below), has confirmed that he is drawing up guidelines for senior civil servants and the parties in case the next election produces a hung parliament with no clear winner, an outcome more and more polls, politicians and pundits are predicting.
Speaking just days before the anniversary of the last election that delivered a hung parliament - 28 February 1974 - Whitehall's top mandarin told MPs on the cross-party Justice Committee that if Labour lost its majority to a hung parliament where the Conservatives had more seats, Gordon Brown should not immediately rush to resign the day after the election.
The Friday removal vans in Downing Street are a traditional British election ritual, but Sir Gus suggested that the Prime Minister should stay in office until it was clear who the Queen should invite to form the next government - a decision in which the role of the Liberal Democrats or the nationalists could be a factor.
"I believe it is the responsibility of the Prime Minister to ensure that the Monarch remains above politics and when the Prime Minister resigns it is very apparent who the Queen should be calling to produce the next stable government ... It is the Prime Minister's responsibility not to resign until that situation is clarified," he said.
But Sir Gus added that, in those circumstances, the 'caretaker' Prime Minister should be barred from making "major" policy announcements that might seek to gain party advantage. Special rules limiting government action would apply, as during an election campaign, until a stable administration was formed. He said there was an urgent need for clarity and these new guidelines would be published.
Those comments, made after consultations with Buckingham Palace, should please constitutional historians and Whitehall-watchers like Professor Peter Hennessy of Queen Mary, University of London, who have warned that the Sovereign's constitutional role in a hung parliament has for too long been "shrouded in mystery", based on mere tacit understandings rather than any published rules.
There have been fears that the Queen could be dragged into political controversy over the decision on which party leader, or conceivably even another senior politician, she should invite to form a government in such uncertain circumstances.
After the Conservative Prime Minister Ted Heath (below) lost his majority in that February 1974 election, he stayed on in Downing Street over the weekend, trying unsuccessfully to agree a coalition deal with Jeremy Thorpe's Liberal Party - events vividly recalled by some of those I interviewed for a BBC Radio 4 series on how to cope with a hung parliament, Hung, Drawn and Thwarted
Politicians I spoke to for these programmes pinpointed as a major weakness the lack of time after an inconclusive general election for parties to negotiate any kind of electoral deal or accommodation, criticising our British preference for an instant handover of power compared to what happens in countries more used to inconclusive election results.
Andrew Mackay, John Major's deputy chief whip in the last Conservative government, called for a breathing space if the election result proves inconclusive:
"All of them will be dog-tired and exhausted and then, immediately, without sleep, to decide what to do isn't in the national interest. This country can run without a government for a week or so."
Sir Gus O'Donnell seemed to be addressing that point when he reminded MPs that a Prime Minister who has, to all intents and purposes, lost the election still has the right to stay in power until defeated in the House of Commons - usually in the vote at the end of the debate on the Queen's Speech setting out the government's plans for new laws.
Mind you, that hasn't happened since before the Second World War!
The Cabinet Secretary's intervention may help avoid a repeat of the scenes witnessed over that long weekend more than 30 years ago, and recounted in the programmes, when the Great and the Good from Whitehall and the Palace were observed taking some very discreet strolls in Westminster's St James's Park, informally discussing how to keep the Queen out of politics!
The Commons Justice Committee is holding a short inquiry into what might happen in a hung parliament, unknown territory for today's generation of politicians and civil servants. No-one is talking seriously about coalitions this time. It all depends, of course, on who wins most seats, and votes - which could be very different. Many are predicting that if the Conservatives had by far the most seats in a hung parliament, then David Cameron would form a minority government and press ahead with his programme, challenging the other parties to vote him down and risk another election.
But if the Queen granted such a Tory request for an early second election, and that produced another hung parliament ... all bets might be off.