A bank says it is entitled to about €1.1 million in fees for its advice in relation to the refinancing of the State's biggest fuel retailer, Topaz Energy Group,which was recently taken over by businessman Denis O'Brien.

Investec Bank was employed by Topaz to provide advisory services in relation to recapitalisation of the group as part of the sell-off of its IBRC loans.

Investec claims that, through its wholly-owned subsidiary, NCB Corporate Finance, it was agreed that advice would be provided on a number of matters.

A fixed fee of €200,000 was agreed with a monthly retainer of €40,000 and a “success fee” of €700,000, it alleges.

Investec says it provided such a service including a presentation to Island Capital, which is ultimately controlled by Mr O’Brien. That included an option for Mr O’Brien to buy the other primary shareholding in Topaz.

In July 2013, Mr O'Brien, through Kendrick Investments Ltd, purchased a majority shareholding. This, Investec says, confirmed the shareholder-led refinancing as per the agreement.Investec now claims the success fee and €200,000 related to advice on a property resource fund.