The fortunes of Bertie Ahern, reportedly the most successful political Irish leader since independence from Britain, has hit rock bottom after he was forced to admit to questionable tax affairs.

Ahern's current problems are related to a long-running public investigation, the Mahon tribunal, into land planning deals linked to political favours.

The Taioseach has suffered days of drawn-out cross-questioning about so-called 'dig-outs' – loans or gifts from rich businessmen, The Times reports.

The tribunal is investigating claims by a developer, Owen O'Callaghan, that he gave substantial sums of cash to Ahern between 1989 and 1992, and a series of payments he received when he was finance minister in the 1990s.

Further reading:

Deloitte's £40m bill shocks Ireland

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