ROYAL Bank of Scotland is closing the arm of its investment bank that advises on mergers and acquisitions after failing to find a buyer for the business.

RBS decided to exit the M&A business as part of its effort to slim down its activities and focus on its core retail and corporate banking activities.

The unit has been involved in recent deals such as the £807 million acquisition of Edinburgh Airport by Global Infrastructure Partners and helped engineering firm Charter International, owner of Renfrew engineer Howden, in its defence before it was sold to US group Colfax for £1.5 billion. But RBS failed to find an investor to buy the business as the M&A market remained subdued.

RBS sold its corporate broking business, Hoare Govett, to US investment bank Jefferies last February.