A tax deal last month between Britain and US Internet giant Google that forced Prime Minister David Cameron on the defensive was "disproportionately small", a group of British MPs said on Wednesday.
The deal coincided with a tax deadline for many Britons and there was an outcry over the amount—£130 million (165 million euro, $181 million) for a decade of Google business in Britain, where it makes 11 percent of its global sales.
"The sum paid by Google seems disproportionately small when compared with the size of Google's business in the UK," the cross-party panel of MPs said.
It expressed concern that Britain's tax-collecting body "appears to have settled for less corporation tax from Google than other countries are willing to accept".
The panel called on the tax agency "to monitor the outcome of other tax authorities' investigations into Google, and re-open its settlement with Google if relevant new evidence becomes available" following ongoing probes in France and Italy.
While finance minister George Osborne has hailed the British agreement a victory, there has been a barrage of criticism, including from within Cameron's own Conservative Party.
It later emerged that Google had made profits of £106 million on revenues of £1.18 billion in Britain in the last 18 months alone and the Labour opposition claimed the giant was paying only "three percent tax".
PAC chair Meg Hillier on Wednesday said "public anger has been palpable ever since this settlement was announced and we still don't know the full details".
Hillier, a lawmaker for the main opposition Labour party, added: "Whether you call it secrecy or confidentiality, this lack of transparency does nothing to build confidence that big corporations are paying their fair share of tax."
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