British American Tobacco (BAT) has retained Slaughter and May as sole legal adviser on a formal investigation by the UK's Serious Fraud Office (SFO) over allegations of bribery and corruption, Legal Week understands.

BAT said in a statement today (1 August) that it is investigating, with its lawyers, "allegations of misconduct", and that it has been informed the SFO "has now opened a formal investigation". BAT said it "intends to cooperate with that investigation".

BAT first appointed Slaughters as its sole legal adviser on the case in December last year.

Previously, the company said it had worked with both Slaughters and Linklaters "for some time" on the case, which was triggered by a BBC Panorama documentary in 2015.

It is understood that the Slaughters team representing BAT continues to comprise its London-based co-heads of investigations Jonathan Cotton and Richard Swallow, and investigations partner Damian Taylor.

The BBC documentary alleged that BAT had paid bribes to officials in east Africa. Since then, US congressmen said additional documents have emerged, which they claim indicate alleged bribery may have been more widespread in Africa.

The company hired Linklaters in February 2016 to conduct "a full investigation" into claims made by Paul Hopkins, a former BAT employee. It is not known when it first appointed Slaughters and the firm declined to comment.

In October last year, the London-listed tobacco giant outlined plans for a merger with Reynolds American, the owner of Camel cigarettes, by purchasing the remaining 57% of the US company it does not already own. It instructed Cravath Swaine & Moore and Herbert Smith Freehills to advise on the merger proposal.

The deal completed last week (25 July).