Mr Brown wants to define the principles that 'bind' Britain

Mr Brown's spokesman said he welcomed debate about a motto like France's "Liberty, Equality, Fraternity".

But he said the prime minister was investigating a longer "statement of values" which could be used as part of any future "Bill of Rights".

Mr Brown has urged a new relationship between government and citizens.

The Daily Mail reported that a five or six word motto could be emblazoned on every public building in Britain - and could even be included on UK passports and birth certificates to boost national pride.

'Mustn't grumble'

It prompted a series of suggestions from BBC News website readers, including; "Unity in individuality", "Mustn't grumble" and "Smile! You're on CCTV".

But Mr Brown's spokesman said the prime minister was concentrating on the "statement of values" outlined in the Governance of Britain Green Paper.

The paper says "public debate" will be used to come up with the statement, intended to reflect "the ideals and principles that bind us together as a nation".

I don't think the prime minister would have any difficulty with a debate on a British motto Mr Brown's spokesman Readers' mottos

The idea is that it will form part of Mr Brown's wider proposals for constitutional change - which include a British "Bill of Rights", or written constitution, that he says will make the government a "better servant of the people".

Asked about reports that a short motto was being planned, Mr Brown's spokesman said: "It's an interesting debate to have.

"The proposal that was set out, however, at the time of the constitutional reform package in July was more around a statement of values which could then feed into any possible British Bill of Rights.

"I don't think the prime minister would have any difficulty with a debate on a British motto, but the proposals the government set out were more around a British statement of values."