The Big Four firm is currently a managing agent on a DfID scheme called the Investment Facility for Utilising UK Specialist Expertise (IFUSE).
According to DfID, IFUSE supplies specialist government-to-government expertise to support business environment improvement in developing countries and regions by helping these countries to encourage more businesses to invest in their country, delivering more jobs, better prospects for economic growth and a greater range of products and services for consumers at more competitive prices.
Abbott argued that given PwC’s involvement in the LuxLeaks tax avoidance scandal, the firm is not a suitable adviser on this scheme.
"As the Luxleaks scandal has shown, PwC is in the business of helping multinational corporations avoid tax. For this reason it is abundantly clear that there is potentially a very serious conflict of interest in DfID paying PwC to administer projects designed to help developing countries raise more tax," she said.
Abbott urged DfID to be more transparent in PwC’s exact role in tax assistance through IFUSE, in pilots for Tax Inspectors without Borders and now the full scheme.
“We need some immediate clarity to know what we are not paying PwC to bat for poor countries' governments while also batting for big business to steal from those governments," she added.
"PwC and Tax Inspectors without Borders must make public, on an ongoing basis, the affiliations of each individual sent to each developing country tax authority, the identities of corporate taxpayers in those countries over whose tax bills they may have had influence, and the identity of the auditors of those firms."
Aboott has raised her concerns a number of times in the House of Commons asking the secretary of state for International Development what proportion of her department spending was paid to the Big Four accounting firms since 2010 and what proportion of her department spending was managed by the Big Four in each year since 2010.
She also queried what proportion of DfID’s spending on issues of tax since 2010 was paid to the Big Four and how much DfID spent on academic research on tax, and civil society work on tax in that time.
Finally, she asked what additional revenues were achieved for developing countries as a result of the pilot scheme for Tax Inspectors Without Borders; and how much such revenue derived from improved tax settlements with clients of the Big Four.
"For a business that claims to provide accountability and transparency, PwC seems to have put itself in a position where conflicts of interest are not only clearly possible, but in fact highly likely. Without transparency how is DFID to know that PwC is not running rungs around them?" Abbott warned.
"Following the Luxleaks scandal, it beggars belief that DFID would use a known facilitator of massive global tax avoidance to administer support work to tax authorities in the world's poorest countries."
A spokesperson for DfID said, “PwC act as managing agents for DFID’s Investment Facility for Utilising UK Specialist Expertise programme but are not involved with advising developing countries, which is carried out by independent experts. As with all our programmes, we have rigorous checks and balances in place to ensure there is no conflict of interest.”
PwC declined to comment.