Police arrested Gillian Gibbons, 54, on Sunday after complaints by parents that she had acted blasphemously in allowing the toy to be called Muhammad. Gibbons, a teacher at the exclusive British-style Unity high school in Khartoum, had asked her pupils to name the bear as part of a project to teach them about animals and their habitats. "The teacher asked me what I wanted to call the teddy," the boy told Reuters. "I said Muhammad. I named it after my name."

His suggestion was put to a class vote and was the clear winner. The boy, who said he was not thinking about the prophet when he put forward his choice, described Gibbons as "very nice".

Gibbons, who is from Liverpool, spent her third night in jail yesterday, as she was moved from a local police station to a bigger police office in Khartoum north, where she is waiting to be charged. She has retained a local lawyer, but embassy officials were prevented from seeing her yesterday.

"She is still in detention and the investigation appears to be ongoing," said a British embassy spokesman in Khartoum. "We visited her on Monday and we hope to be allowed to see her again tomorrow morning."

Gordon Brown said yesterday that he felt "very sorry for what has happened to Miss Gibbons", and that every effort was being made to ensure a speedy release. The Muslim Council of Britain also condemned the arrest, saying it was "obvious that no malice was intended".

The Sudanese government is insisting the law follow its course. Mohamed al-Mardhi, the justice minister, told local media that he had ordered the country's general prosecutor to take charge of the case. "[The charges] are under the Sudanese penal code ... insulting religion and provoking the feeling of Muslims," he said. The offence carries a penalty of six months in jail or 40 lashes.

The teddy bear incident occurred in September, a month after Gibbons arrived in Sudan, but it was not until last week that Unity's director was informed that a few parents had complained to the Ministry of Education that their religion had been insulted. For devout Muslims, any depiction of the prophet Muhammad is regarded as blasphemous.

The school is closed until January, for fear of reprisals. The feeling among most teachers and parents at Unity - Muslim and non-Muslim - is that the Sudanese authorities have overreacted.

"I'm annoyed ... that this has escalated in this way," Muhammad's mother said. "If it happened as Muhammad said, there is no problem here - it was not intended."

An English mother, who had a child in one of the other classes in Unity, said: "I was just gobsmacked. And when I talked about it to colleagues who were Muslims, they felt the same. They were amazed.

"When I first heard about the teddy bear I thought 'Oh no, don't go down that road. That's a really bad idea.' But she had just arrived in Sudan. She must have been idealistic, full of new ideas. She just didn't realise that it was such a problem."

Even the Sudanese embassy in London called it a "storm in a teacup". Khalid al-Mubarak, the embassy spokesman, told the BBC he expected the case would be treated as a "minute complaint", and that cultural differences had caused the problem.