Iran's president Mahmoud Ahmadinejad has accused Barack Obama of behaving like his predecessor towards Iran and said there was not much point in talking to Washington unless the US president apologised.
Mr Obama said on Tuesday he was "appalled and outraged" by a post-election crackdown and Washington withdrew invitations to Iranian diplomats to attend Independence Day celebrations on 4 July.
"Mr Obama made a mistake to say those things ... our question is why he fell into this trap and said things that previously (former president George W.) Bush used to say," the semi-official Fars News Agency quoted President Ahmadinejad as saying.
About 20 people have been killed in protests after President Ahmadinejad was re-elected in a disputed 12 June poll which opposition leader Mirhossein Mousavi says was rigged.
Mr Mousavi said he was under pressure to stop challenging the election result and also complained about the closure of his Kalameh-ye Sabz daily newspaper and arrest of its staff.
His website said 70 professors were detained after meeting Mousavi and his campaign manager arrested.
Iran has jailed around 40 journalists and media workers in the post-election crackdown, New York-based media watchdog the Committee to Protect Journalists said on Thursday.