A senior executive with the Norwegian company Telenor has rejected evidence by Mr Denis O'Brien.
Mr Arve Johannson gave evidence about the recoupment by Telenor of a 1996 payment of $50,000 to Fine Gael.
The money was recouped from ESAT Digifone, in which Telenor had a 40 per cent shareholding.
Mr O'Brien has said Telenor "forced" Digifone to recoup the money during a difficult shareholders' agreement negotiations in 1996, but Mr Johannson said this is not the case.
There was no mention of the matter in the documents which record the negotiations in 1996 and the $50,000 was not an issue, he said.
He also differed with evidence earlier this year from Mr O'Brien, who said he knew nothing about the invoices sent to Telenor by the late Mr David Austin seeking $50,000 for consultancy work. These were to cover the political payment.
Mr Johannson said Mr O'Brien asked him to make the payment on behalf of Digifone and he was told Telenor would be reimbursed.
When Telenor received an invoice from the late Mr Austin for "consultancy work" and a request that the money be lodged to an offshore account, Mr Johannson said, he showed this documentation to Mr O'Brien during a meeting in Dublin.