The Forum issued a statement received by Aljazeera.net in which it condemned the arrest of notable Iraqi politician Abd Al-Jabbar al-Kubaisi.
Al-Kubaisi, who is a leader of the Iraqi National Alliance, was arrested in a Saturday pre-dawn raid by US troops backed by armoured vehicles and helicopters. They surrounded his home in Baghdad and took him to an undisclosed destination.
Unconfirmed reports suggested that al-Kubaisi arrived to Amman, Jordan on 26 August, where his passport was held for a week before he was allowed to continue to Baghdad.
The statement claimed al-Kubaisi's arrest politically motivated and against democratic values. It also condemned the closure of Aljazeera's Baghdad office, and accused the interim government of oppressing "anti-occupation voices".
It called for al-Kubaisi's immediate release.
Al-Kubaisi is known for his moderation. He opposed the government of Saddam Hussein but did not support the UN sanctions against Iraq, UK-US made no-fly zones, and the war in 2003.
The then France-based opponent was among dozens of Iraqi dissidents who travelled to Baghdad in 2003 before the war on Iraq and met Hussein.
The delegation agreed with Hussein that they would defend the country against a US-led invasion, provided they could discuss their differences with him after the war.
The Arab National Forum made a plea to Amr Mousa and Kofi Annan the respective secretary-generals of the Arab League and the UN.
"Mousa and Annan have to tackle their duties in standing against the occupiers in Iraq who are launching assassination and random arrest campaigns, armed by resolutions, that do not comply with international law and the UN charter" the statement said.
The statement also called on to the Union of Arab Engineers to support al-Kubaisi who is a veteran Iraqi engineer.
Khalid al-Sufiani, the coordinator of Beirut-based People's Association for the Support of Iraq, stated in a letter sent to Aljazeera.net that the arrest could not be dealt with separately, it comes amongst a "fierce campaign" by the interim Iraqi government to suppress Iraqis in Tal Afar and al-Latifiya.
"Let the arrest of the notable revolutionary politician Abd Al-Jabbar al-Kubaisi be the start of an Arab and international campaign to unearth the destiny of tens of thousands of detainees in the prisons of the US occupation in Iraq" the letter said.