Mahmoud Ahmadinejad has been sworn in for a second term as Iran's president, nearly eight weeks after a landslide election victory disputed by opposition candidates.
Ahmadinejad took the oath of office before parliament on Wednesday, as opposition protesters attempted to gather on the streets of Tehran, the capital.
"The June 12 epic is the start of major change in Iran and in the world," Ahmadinejad said after being sworn in.
At least 20 people were killed and about 2,000 arrested after claims that the June 12 election was rigged sparked a series mass demonstrations on the streets of Tehran.
Heavy security
Hundreds of police and members of the pro-government Basij militia were deployed outside parliament in an apparent attempt to stop any demonstrators from gathering, witnesses said.
One witness told the Reuters news agency that hundreds of protesters were walking around the parliament building.
"But there is no clash," the witness said. "Mobile phones have been cut off."
However, another witness told the AFP news agency that security forces used pepper spray against protesters in Baharestan square, near to the parliament building.
"The protesters were chanting anti-Ahmadinejad slogans. The police and the Basijis dispersed them. All the nearby shops are closed," the witness said.
During Wednesday's ceremony, Ahmadinejad criticised Western nations, several of which - including the United States, Britain, Italy, Germany and France - have declined to offer formal congratulations on his re-election.
"We heard that some of the Western leaders had decided to recognize but not congratulate the new government ... Well, no one in Iran is waiting for your messages," he said.
"We will resist oppressors and try to correct the global discriminatory mechanisms in order to benefit all the nations of the world."
On Tuesday, the White House, which Iran has repeatedly accused of interfering following the presidential polls, finally announced that it considered Ahmadinejad to be Iran's elected leader.
Western 'snub'
Mehrdad Khonsair, a former Iranian diplomat told Al Jazeera: "He feels that this snub [from Western leaders] is such that he's had to respond ... it shows obvious disappointment.
"He essentially pointed out that negotiation with him in the future is going to be difficult," he said.
Khonsair said that Ahmadinejad also sought to highlight the backing that he enjoys amongst the dominant political powers in Iran.
"He was saying he has the support of the important elements in Iran needed to implement his policies for the next four years," he said.
The dispute over the election has exposed divisions in Iran's ruling elite, with Ayatollah Ali Khamenei, Iran supreme leader, endorsing the poll and backing Ahmadinejad, while other leading political figures supported opposition calls for a re-run.
Ayatollah Mahmoud Hashemi Shahrudi, the head of Iran's judiciary, called for unity amid speculation that reformist MPs could boycott the swearing-in.
But Mir Hossein Mousavi, who came in second in the presidential race, and Mehdi Karroubi, another defeated reformist candidate, have both vowed to continue their protests against Ahmadinejad's election.
Ahmadinejad will have two weeks to present a cabinet of ministers to the conservative-dominated assembly for approval after Wednesday's ceremony.
PHOTO CAPTION
Iranian President Mahmoud Ahmadinejad, right, waves as he arrives for the swearing-in ceremony for his second term as judiciary chief Ayatollah Mahmoud Hashemi Shahroudi makes his way in an open session of parliament in Tehran, Iran, Wednesday, Aug. 5, 2009.
Al-Jazeera