By Ahmed Rasheed and Saif Hameed

BAGHDAD (Reuters) - Iraqi Prime Minister Haider al-Abadi on Tuesday said six lawmakers accused of corruption in the defense sector would not be allowed to travel abroad until a parliamentary committee had completed an investigation.

Defence Minister Khaled al-Obeidi on Monday accused Parliament Speaker Salim al-Jabouri and five other MPs of lobbying for businesses seeking contracts to sell overpriced planes, vehicles and other goods to the armed forces. He said they sought to influence ministry appointments and some tried to blackmail him. All six deny the accusations.

The scandal comes at a critical time for Iraq as its armed forces gear up to recapture Mosul, the capital of Islamic State in Iraq, in what is meant to be a final push to defeat the militants.

Earlier on Tuesday, parliament appointed a committee to probe the allegations, which will begin its work on Wednesday, the parliament's Integrity Commission head Talal al-Zobaie told Reuters.

"This matter caused an earthquake in parliament," he said.

Separately, Abadi announced the six MPs, four men and two women, would not be allowed to travel until the investigations were completed.

Obeidi made his announcement while appearing before parliament on Monday to respond to separate corruption allegations at his ministry. He previously called his summons to address MPs a "conspiracy by the corrupt."

The Iraqi defense ministry has been accused by lawmakers of wasting billions of dollars in public funds and weakening the armed forces to the point where they collapsed in 2014 in the face of the Islamic State threat.

This allowed Islamic State to seize a third of Iraqi territory, but the group has since been pushed out of many of those areas by Shi'ite Muslim militias and a military that is slowly being rebuilt with the support of a U.S.-led coalition.

Abadi's efforts to combat corruption in government have been met with resistance and caused major disruption to Iraqi politics.

Iraq, which ranks 161 out of 168 on Transparency International's Corruption Index, but has faced resistance from within the political elite.

(Writing by Maher Chmaytelli; Editing by Raissa Kasolowsky)