Mahmoud Ahmadinejad has been sworn in for a second term as Iran's president, after weeks of post-election unrest.

经历数周选举的动荡之后，Mahmoud Ahmadinejad宣誓继任伊朗总统。

In an address after the ceremony, he criticised foreign powers who have cast doubt on the validity（有效性，正确性） of the election, saying Iran would resist them.

Opposition¹ supporters protesting outside parliament were met by hundreds of riot police（防爆警察）.

Germany, France, Britain and the US all said they would not be sending letters of congratulation to Mr Ahmadinejad.

At least 30 people died during the street protests which followed the 12 June poll.

Mr Ahmadinejad now has two weeks to form a government that must then be approved by parliament.

'We will resist'

Taking his oath of office（就职宣誓）, broadcast live on state TV, Mr Ahmadinejad promised to "protect the official faith, the system of the Islamic revolution and the constitution".

In the address that followed, he called for "a national will, a national resolve", and told his audience: "We need to join forces."

"I do not have any incentive²（刺激的，鼓励的） other than serving the people and the country and I do not think of anything but the progress and development of the nation," Mr Ahmadinejad said.

Following the swearing-in, he used his first address to defend the official results of the election - which gave him an overwhelming victory - and criticised Western powers' response to the disputed poll.

"Some governments should feel responsible for their words and deeds," he said.

"The people of Iran are for a constructive³ dialogue... We will resist violations⁴ of law and abuse...

"[Foreign governments] just want democracy at the service of their own interests - they do not respect the rights of other nations. They see themselves as the yardstick⁵（码尺） of democracy - our people oppose this, that's what our people are resisting," he said.

Several states which have criticised the elections said they would not be sending customary letters of congratulations to Mr Ahmadinejad to mark his reappointment as president, including the US, Germany, France and the UK.

"Nobody in Iran is waiting for anyone's congratulations," said Mr Ahmadinejad, to the laughter of listening deputies.

Outside, hundreds of demonstrators gathered. There were reports of clashes with riot police and at least one arrest.

Khamenei endorsement⁷

There were some notable（显著的，著名的） absences for Wednesday's inauguration⁸ ceremony, though envoys⁹ from the European Union and the UK did attend.

Mr Ahmadinejad's predecessors¹⁰ as president - Mohammad Khatami and Akbar Hashemi Rafsanjani - were missing, as they were from a formal ceremony to endorse⁶ his presidency¹¹ on Monday.

Also missing were two defeated opposition candidates - Mir Hossein Mousavi and Mehdi Karroubi - who continue to contest the results.

In addition, a reformist faction¹² of about 70 MPs said only about 13 of its members attended - and some of those who did attend reportedly left during Mr Ahmadinejad's speech in a show of protest.

Mr Ahmadinejad has received the backing of Supreme¹³ Leader Ayatollah Ali Khamenei, who has supported him throughout the unrest.

Mr Khamenei said Mr Ahmadinejad was the rightful winner and that Iranians had "voted in favour of a fight against arrogance¹⁴, to confront destitution¹⁵ and spread justice".

Meanwhile in the US, White House spokesman Robert Gibbs retracted¹⁶ his description of Mr Ahmadinejad as the "elected president" of Iran.

Mr Gibbs said he had misspoken and that the US would leave it up to the Iranian people to decide whether the election was fair.

The BBC's Tehran correspondent, Jon Leyne, says forming an acceptable, credible¹⁷ government could be the real challenge for the Iranian president.

Mr Ahmadinejad has been dogged by controversy¹⁸ in recent weeks, becoming embroiled¹⁹ in（卷入） a series of disputes with conservative politicians who would normally be his allies.

More than 100 people, including some members of the opposition movement, went on trial in Iran on Saturday for their alleged²⁰ involvement in the post-election violence.

Foreign media, including the BBC, have been restricted in their coverage²¹ of Iran since the election protests turned into confrontations²² with the authorities in which at least 30 people were killed.