Three of HMRC's top officials are due back in front of the Public Accounts Committee (PAC) this afternoon, when they are expected to face questions over the tax treatment of large multinationals such as Google, Amazon and Starbucks.

Edward Troup, HMRC tax assurance Commissioner, who is responsible for overseeing settlements in sensitive tax disputes, will be appearing, along with Jim Harra, director-general business tax and Jennie Granger who is HMRC's director general enforcement and compliance. The meeting is scheduled for 3.30pm.

All three are likely to be asked about emails that have emerged since a previous hearing and which appear to cast doubt on some of the ways Google has limited its UK tax bill. According to the emails, which were passed to HMRC by a former Google employee, although the online giant claimed not to be running a sales operation in the UK, staff here were closely involved in selling advertising, the revenues of which were booked through the company's Irish business in order to reduce its corporation tax liability.

PAC chair Margaret Hodge has described this approach as 'highly contrived' and called on HMRC to look more closely at the complex tax policies used by multinationals. Today's hearing is also likely to question the ability of major foreign companies to enter into so-called 'sweetheart' deals with HMRC.