As schoolteacher Gillian Gibbons’ lawyers prepare an appeal against a 15-day jail sentence imposed in Sudan over the naming of a teddy bear, Muslims in Britain have joined in condemning the decision and calling for clemency.

The Muslim Council of Britain (MCB) declared: “This case should have required only simple common sense to resolve. It is unfortunate that the Sudanese authorities were found wanting in this most basic of qualities. They grossly overreacted in this sad affair… Gillian should never have been arrested, let alone charged and convicted of committing a crime.”

“We hope that Gillian will be able to return home without much further delay,” added Dr Muhammad Abdul Bari, Secretary-General of the Muslim Council of Britain.

Of the original decision to prosecute he said: “This is a disgraceful decision and defies common sense. There was clearly no intention on the part of the teacher to deliberately insult the Islamic faith… We call upon the Sudanese President, Omar al-Bashir, to intervene in this case without delay to ensure that Ms Gibbons is freed from this quite shameful ordeal.”

The Islamic Human Rights Commission and the Ramadhan Foundation have also protested.

Ms Gibbons, aged 54, from Liverpool, has been sentenced to just over two weeks in prison and deportation for the ‘offence’ caused by allowing a toy bear in a class of 6 and 7 years olds to be named Muhammad.

The name is a common one, and a boy in the class said that the bear was named after him, not the Prophet of Islam. But the issue rapidly became a political football as Islamists pressed for action, and elswhere in the world people and politicians (including many Muslims) expressed incredulity and outrage.

A spokesperson for the Sudanese diplomatic mission in Britain said that in his culture a teddy bear was not a harmless child’s comfort but a “wild anaimal” – a claim dismissed as “nonsense” by other Sudanese commentators.

The teacher escaped conviction for inciting hatred and showing contempt for religious beliefs, which would have carried a more serious sentence – up to a year in jail and 50 lashes.

The UK Foreign Office has been in contact with Sudan’s government overnight and will repeat demands for her release.

Archbishop of Canterbury Dr Rowan Williams said he could not “see any justification” for the sentence, calling it an “absurdly disproportionate response” to a “minor cultural faux pas”.

Chris Ball, a friend and former colleague of Mrs Gibbons, told the BBC she had been “the victim of global political circumstances” and said the guilty verdict was “devastating”, although “it could have been a lot worse”.

Catherine Wolthuizen, chief executive of Fair Trials International, said 15 days in a Sudanese prison for an “innocent misunderstanding” is “a serious and harsh punishment indeed”.

Inayat Bunglawala, assistant secretary general of the Muslim Council of Britain, said it appeared to have been a “quite horrible misunderstanding” and Ms Gibbons should never have been arrested.

Sudan’s top clerics had called for the full measure of the law to be used against Ms Gibbons and labelled her actions part of a “Western plot against Islam”.

But Islamic Human Rights Commission chairperson Massoud Shadjareh said: “Both the Sudanese government and the media must refrain from using Islam and Islamic principles to legitimise this fiasco, which may result in the unjust conviction of an innocent person, and which will only lead to the promotion of Islamophobia and further demonisation of Islam.”

A spokesperson for the Muslim youth organisation, the Ramadhan Foundation, added: “this matter is not worthy of arrest or detention and her continued detention will not help repair the misconceptions about Islam.”