TEHRAN (AFP/Reuters) - President Mahmoud Ahmadinejad warned his US counterpart Barack Obama on Thursday to stop meddling in Irans affairs as the regime clamped down further on the opposition despite growing global concern. Opposition leader Mir Hossein Mousavi said he was under pressure to withdraw his complaints of widespread irregularities in the vote he lost to Ahmadinejad, with his website reporting that scores of supporters had been rounded up. Mousavi, a former premier who emerged as a strong contender for president and has since led a massive public protest campaign over what he brands a shameful fraud has demanded the results be scrapped and a new vote held. The recent pressure on me aims to make me give up my demand for the election to be cancelled, Mousavi said on his Kalameh website. My access to people is completely restricted. President Mahmoud Ahmadinejad accused Barack Obama on Thursday of behaving like his predecessor towards Iran and said there was not much point in talking to Washington unless the US president apologised. I hope you (Obama) will avoid interfering in Irans affairs, Ahmadinejad said, accusing the US leader of using words similar to those of his predecessor George W Bush who took a hard line against the Islamic republic. Will you use this language with Iran (in any future dialogue)? If this is your stance, there will be nothing left to talk about, said Ahmadinejad. Since taking office Obama has made diplomatic overtures towards Iran, after three decades of severed ties and a standoff with the international community over Tehrans nuclear drive. But he has been increasingly critical of the June 12 vote and said he was appalled and outraged at the crackdown on protesters who have staged mass demonstrations against the election. Reports said on Thursday that Iran has jailed more than 140 prominent political activists, journalists and university lecturers since the election, including Mousavi supporters. The authorities have also spoken of arrested many hundreds of protestors over the unrest, including some people it said had British passports. The Revolutionary Guards, the elite force set up to protect the Islamic republic, has already warned of a decisive and revolutionary riposte to any further protests. Neither side can claim victory now, said an analyst in Tehran, who declined to be named. This path is very corrosive. Both sides are tired. What the system needs is to have some mediators, who can convince both sides to agree over a middle way, he said. Meanwhile, G8 foreign ministers headed Thursday into three days of talks in the Adriatic city of Trieste that could yield a firm condemnation from the world powers of Irans crackdown. Tensions have been rising between Iran and the West over the Islamic regimes suppression of mass street protests sparked by President Mahmoud Ahmadinejads contested re-election. Reaching consensus on Iran was shaping up as a delicate diplomatic exercise with G8 member Russia insisting that the post-election turmoil was an Iranian internal matter. Meanwhile, British Foreign Secretary David Miliband said Thursday there is a crisis of credibility between Irans government and its people, lamenting the profound clampdown on protests over disputed elections. Miliband added that London will press Iranian authorities over an Anglo-Greek journalist detained in the Islamic republic. There certainly has been a profound clampdown in Iran... youve seen that with the clampdown on journalists as well as the attacks on foreigners, he told the BBC. Meanwhile, Qatars prime minister said the unrest gripping Iran in the aftermath of its presidential election was a domestic affair but that the stability of the Shiite-majority country is vital to the Gulf region. Meanwhile, the Spanish parliament on Thursday called on Iranian authorities to release opposition activists and end the repression against the civilian population. The congress of deputies calls for the immediate release of the opponents of the regime who have been arrested, the parliament said in a resolution. Meanwhile, Hezbollah accused the West on Thursday of fomenting protests in Iran over this months presidential election but added that it had no worries about the stability of its main foreign backer. The extent of Western and American involvement in Irans internal affairs is now clear, the Shiite militant groups deputy leader, Sheikh Naim Qassem, told AFP in an interview. What is going on in Iran is not a simple protest against the results of the presidential election, he said. There are riots and attacks in the streets that are orchestrated from the outside in a bid to destabilise the countrys Islamic regime. Meanwhile, the newly-appointed head of the US Southern Command, General Douglas Fraser has warned that Irans growing influence in Latin America is a potential risk to the region. Fraser, who on Thursday takes charge of US military operations in 31 countries across Latin America and the Caribbean, expressed real concern about the Islamic Republics links with extremist organizations in the region. The real concern is not a nation-to-nation interaction, it is the connection that Iran has with extremist organisations like Hamas and Hezbollah and the potential risk that that could bring to this region, Fraser told journalists ahead of taking up the post. Commenting on Irans ties to extremist groups in the region, Fraser said: it is a concern, and it is an issue we will continue to monitor for any increasing activity. He cited Lebanon-based Hezbollah, which has links to Iran and is accused of being behind a suicide bombing that killed 200 US marines in Beirut in 1983 and the 1996 bombing of the Khobar towers in Saudi Arabia, which killed more than 20 people.