The company, led by chairman John Teeling and chief executive David Horgan, said the stakeholders wanted to raise their holding in the company for some time.
The capital was raised through the placing of 4,090,000 shares at a price of 45p.
One of the institutions involved in stake building also arranged the placing, the company said.
Petrel, which is active in the international oil scene, said the funds will be used as working capital to advance its projects in Iraq.
The group is involved in both oil exploration and development in that country.
It said the amount raised should fully cover the company’s existing and anticipated working capital requirements till the end of 2010.
Following the placing there will be 76,664,624 shares in issue.
Managing director David Horgan, said that as access and returns from oil shrink elsewhere, Iraqi oil was never more attractive. “Put simply, Iraq offers the perfect package of the lowest exploration costs combined with the lowest production costs anywhere in the world.
“Iraqi structures are large, oil quality is excellent and exploration success are the best worldwide for massive structures of this type.
No western company has more on-the-ground experience in that market, he said.
Though the challenges “have been and remain inherent with Iraqi operations, we have never had material security; political or geopolitical concerns”, he said.
The group remains committed to working with the government of Iraq, he said.
The group said that “after an extended period of consolidation which has seen oil production stagnate, the Iraqi oil sector is beginning to overcome its challenges”.
Petrel continues to work closely with the Iraqi Ministry of Oil on existing contracts to resolve outstanding commercial issues to update the scope of work and schedules in line with changing needs and potential new opportunities.