A Swedish newspaper on Wednesday defended its publication of a drawing depicting the head of the Muslim Prophet Mohammad on the body of a dog, following an official protest from Iran.

Daily Nerikes Allehanda published the drawing last week, prompting the Iranian government to summon Sweden's charge d'affaires in Tehran on Monday to object to what it called a disrespectful drawing.

The drawing was by Swedish artist Lars Vilks and was part of a series which art galleries in Sweden had declined to display. The newspaper published the image in what it called a defence of free speech.

"This is unacceptable self-censorship," the newspaper wrote in an editorial on its Web site on Wednesday, referring to the reluctance by galleries to exhibit Vilks's drawings.

"The right to freedom of religion and the right to blaspheme religions go together," it wrote.

Last year, Muslims around the world launched a firestorm of protest after a Danish newspaper published cartoons of the Prophet Mohammad that were reprinted by other European newspapers.

Sweden's Muslim Council, an umbrella organisation for Islamic groups in the country, took issue with Nerikes Allehanda's arguments.

Helena Benauda, chair of the council, said she was surprised because the newspaper had been involved in a dialogue with Muslims following the Danish controversy.

"I think they did understand our point of view -- that you should not publish pictures that could be seen as racist, xenophobic or anti-Semitic," Benauda told Reuters.

Ulf Johansson, editor-in-chief of Nerikes Allehanda, said there was a difference between how his newspaper was approaching the issue and the Danish case.

"This newspaper has always been very eager to defend Muslim rights in Sweden and freedom of religion overall. But we are also very clear that the freedom of speech goes hand-in-hand with that."