Buying a present for the person who has everything is always difficult. But when you’re trying to decide what to buy for the men and women who rule the world, it is damn near impossible.

In fact so sensitive is the question of who gets what (and who gets nothing) when Tony Blair shops for his friends on the world stage that Downing Street has declared Prime Ministerial gift-giving an official secret.

In response to a request from The Times for details of the gifts given by the Prime Minister to President Bush since 2001 Downing Street showed remarkable frankness.

“To provide details of gifts given by the Prime Minister would be wholly inappropriate as it would cause offence and would be discourteous to recipients,” Nicholas Howard, a Downing Street official, said.

“The publication of such information would lead to speculation about why a particular gift was given, yet another head of state or government received a gift of a different value or no gift at all.”

The freedom of information application was made after the President and Mr Blair were overheard discussing the gift of a sweater to Mr Bush during the infamous “Yo Blair” conversation at the G8 summit in St Petersburg in July. But in refusing the request under section 27(1)(a) of the Freedom of Information Act — that disclosure “would be likely to prejudice relations between the United Kingdom and any other state” — Downing Street has prized open a can of worms.

The revelation that some world leaders get less expensive gifts than others and that some receive “no gift at all” will surely set diplomatic channels buzzing. Fuel will be added to the fire because the United States Government already publishes details of the gifts given to President Bush — including some of those presented by Mr Blair and his wife, Cherie. Mr Blair’s listed offerings have included a leather toiletries bag embossed with the president’s initials and a St Andrews Links gift box complete with tartan golf towel and magnetic divot tool.

If the leader of the free world gets this kind of expensive kitsch, one cannot but wonder what might be hidden inside Kim Jong Il’s gift wrapping.

The White House has also declared receipt from Mr Blair of a Conway Stewart leatherette gift box including Churchill fountain pen, cigar, book of quotations and a bottle of ink. This might well cause consternation at the Elysée Palace: President Chirac received the Churchill fountain pen but not the full boxed set from Mr Blair on his 70th birthday.

Mr Blair clearly likes the pen — he received one himself as a gift from the manufacturers in 1998 — but why did his US ally receive the gift set while his cross-Channel adversary got just the pen? And what of Angela Merkel, John Howard, or Silvio Berlusconi? Have they received the PM’s favourite pen, or have they had the rollerball version, or a cheaper make? And who are those who received “no gift at all” (or just a Downing Street Biro)? It is difficult to understand why the Blair gift catalogue is a secret given that the White House publishes much of it. Maybe British gifts are a tad unimaginative in comparison with those from other leaders. King Abdullah of Jordan has given the President six jars of “various fertilisers”, while the Sultan of Brunei’s gifts included a DVD of Singing in the Rain and the President of Tunisia offered a large box of dates.

The Blair offerings are not out of step with the ideas of his predecessors. John Major gave President Bush’s father a cricket bat and presented President Clinton with a Surrey County Cricket Club cap and three umbrellas. Meanwhile, whether it is “discourteous” or not, Whitehall publishes gifts worth more than £140 which are given to Mr Blair and his ministers. Most are held by the ministers’ offices because otherwise the individuals have to purchase them. In recent years Mr Blair has balked at paying from his own pocket for watches, dressing gowns, ceremonial daggers, guitars, rugs and fine wines.

Interestingly, however, no gifts to Mr Blair from President Bush have appeared on the Cabinet Office list between July 2001 and March 2006. Perhaps Dubya is canny enough to keep them under the price limit and, therefore, keep them hidden.

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