Ebadi is the 11th woman to win the peace prize
The Iranian human rights activist who won this year's Nobel Peace Prize has called on the government in Tehran to free all political prisoners.
Shirin Ebadi told a news conference the most urgent issues for Iran to deal with were freedom of speech and the release of those imprisoned for expressing their opinions.
Ms Ebadi, 56, is a well-known lawyer noted especially for promoting the rights of women and children by seeking changes in Iran's divorce and inheritance laws.
She is the first Muslim woman to be awarded the prize, beating other nominees who included Pope John Paul II and former Czech President Vaclav Havel.
The Norwegian award committee said it chose her because of her focus on promoting human rights and democracy in her country.
In Tehran, a foreign ministry spokesman said her award was a cause for happiness and reflected the improved situation of women in Iran.
The BBC's Jim Muir in Tehran says that while Iran's reformists will be delighted, the conservative authorities see the award as a political move by Europe to increase pressure on Iran.
Tribute to courage
Ms Ebadi was the first female judge in her country, but was forced to resign following the Islamic Revolution in 1979.
She said the award, which comes with prize money of $1.3m, had been a surprise but that she was "very happy and glad" about it.
"I hope it will have an effect in Iran.
"As a person who has actively been involved in human rights, I am against war and conflict, and countries and nations do not need war," she said speaking at a news conference in Paris - where she is visiting - hours after the award was announced.
The chairman of the five-member selection committee, Ole Danbolt Mjoes, paid tribute to Ms Ebadi's work at home and abroad, saying she understood that "No society can be seen as democratic without women being represented".
She was also praised as a "courageous person" who "has never heeded the threat to her own safety".
The Nobel committee emphasised that its choice should be seen as a statement about human rights.
"This is a message to the Iranian people, to the Muslim world, to the whole world, that human value, the fight for freedom, the fight for rights of women and children should be at the centre," Mr Mjoes said.
"I hope the award of the peace prize to Ebadi can help strengthen and lend support to the cause of human rights in Iran," he added.
Iranian state media reported the Nobel committee's decision without comment.
LAST 10 YEARS OF WINNERS
2002 - Former US President Jimmy Carter
2001 - United Nations Secretary General Kofi Annan
2000 - Former South Korean President Kim Dae-jung
1999 - Medecins Sans Frontieres
1998 - David Trimble and John Hume, Northern Ireland
1997 - Jody Williams and the International Campaign to Ban Landmines, United States
1996 - Carlos Filipe Ximenes Belo and Jose Ramos-Horta, East Timor
1995 - Joseph Rotblat, Britain, and the Pugwash Conferences on Science and World Affairs
1994 - Palestinian leader Yasser Arafat; Yitzhak Rabin and Shimon Peres, Israel
1993 - Nelson Mandela and FW de Klerk, South Africa
The BBC's correspondent in Tehran says that for the Iranian to win is an enormous boost for human rights campaigners there and a source of great delight to her supporters - but also something of an embarrassment.
"Hardliners who run the judiciary will see it as outsiders now trying to intervene in Iranian politics.
"It is an embarrassment to them to see someone they have vilified held up as a shining example," he said
The choice of Ms Ebadi - the 11th woman and third Muslim to net the prize - surprised observers worldwide. Pope John Paul II was the bookies' favourite to scoop the prestigious award this year amid speculation that he is nearing death.
Official reactions outside Iran have been overwhelmingly positive, and even the Vatican is, reportedly, sending a message of congratulations.
However fellow Pole Lech Walesa - a former president and Nobel laureate - did not seek to hide his disappointment, calling the decision a "big mistake".
"I have nothing against this woman, but if there is someone alive in the world who deserves this distinction it is certainly the Holy Father", he told Polish television.