Small oil firm Leni Oil & Gas may launch legal proceedings against its former partner in an exploration licence off the coast of Malta, days after that partner brought in big player Genel Energy to look for oil on the block.

Leni said on Monday it wanted more information from Mediterranean Oil & Gas on the prospectivity of the oil block, named Malta Area 4, in which it sold its 10 per cent interest in August.

Should that information not be provided by Monday evening, Leni said it had instructed its lawyers to seek disclosure through the courts and to look into whether the sale contract could be undone.

In a statement issued late Monday afternoon, MOG refuted Leni's suggestion that the company misrepresented its position.

"As such, MOG has instructed its legal advisors to address directly the matters raised by Leni, as appropriate, and to uphold and enforce MOG's rights," the company said in the statement.

After buying Leni's stake, MOG went on to sell a majority stake in the block to Genel, a high-profile oil firm formed in 2011 when former BP Chief Executive Tony Hayward and financier Nathaniel Rothschild's bid vehicle bought Turkey's Genel Enerji.

"Leni would not have sold its interest for $1 plus liabilities had it been aware of interest from Genel Energy or other potential farm-in partners," Leni said in a statement.

Leni's executive chairman, smallcap entrepreneur David Lenigas, was previously the chairman of MOG.

Genel Energy, which has a market capitalisation of $3.02 billion, paid $10 million for a 75 percent stake in the block and said it would fund the cost of drilling the first well on it plus the cost of drilling a second well up to $30 million.