Google has denied accusations from MPs that it minimises the amount of tax paid in Britain, claiming that all sales staff operate out of Dublin rather than being based in the UK.
Google's sales in the UK are worth £3.2bn, but the firm only paid £6m in corporation tax in 2011.
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Speaking in front of parliament's Public Accounts Committee (PAC) last November, Google's European boss, Matt Brittin, said all sales staff were based in Ireland, where corporation tax is just 12.5 per cent, nearly half of the current 23 per cent rate in the UK. However, an investigation by Reuters suggested Google sales staff are in fact based in the UK.
"It was quite clear from all that documentation that the entire trading process and sales process took place in the UK," said Margaret Hodge MP, chair of the PAC.
"We will continue to have whistleblowers until we get to the bottom of the truth about all this."
But Brittin, once again giving evidence to the committee, repeated the same argument he gave to MPs in November.
"I stand by what I said. I described very clearly how we operate," he said. "When we came to Europe, we set up Dublin as our European headquarters.
"We wanted to be able to contract with customers across the whole of Europe, not just the UK," he continued, adding "any customer that spends with us, they have to buy from Ireland, because that's where the intellectual property sits."
But Hodge told Brittin she'd seen evidence suggesting that UK staff were in fact closing deals, contrary to what the Google boss had previously explained to the committee.
"This is a UK sale and should be subject to UK tax. I would ask you to reconsider what you are telling us, because it doesn't make sense to your own staff, it doesn't make sense to the committee, it doesn't make sense to any of your clients," she said.
"We all accept the billing is in Ireland. If sales activity is taking place in the UK, you are misleading both parliament and the taxpayers in suggesting that is not happening," Hodge added.
In her closing remarks, she called Google's behaviour devious, calculated and unethical, but the web firm insists it's operating within the rules set by governments and legislators.
