RTE did no favours for Century Radio because Gay Byrne was considering leaving to join Century, Mr Oliver Barry told the tribunal.
RTE threatened it would remove Mr Byrne from the Late Late Show if he joined Century, he added.
Mr Barry also said he never gave up hope of getting Mr Byrne to work for Century Radio and handed him a bank draft worth £1 million in the hope he would join.
"Let me assure you RTE did Century Radio no favours whatsoever from the first day that they learned that Gay Byrne may leave the station and join Century," Mr Barry said.
Mr Patrick Hanratty SC, for the tribunal, asked Mr Barry if he arrived at Mr Byrne's house with the draft and asked him to keep it overnight.
"That's a bit of gossip . . . I can't remember asking him to keep it overnight. I asked him to take it," Mr Barry replied.
Although Mr Byrne had decided not to join Century, Mr Barry thought he might still persuade him.
"I thought once we got the licence we'd get him back in. Money talks in that business, you know."
Mr Hanratty said Mr Byrne signed a new contract with RTE on January 16th, 1989 - two days before Century was awarded the national radio licence.
Mr Barry said he was unaware Mr Byrne had signed a contract at that stage. "Good luck to him and I hope he got a very handsome contract . . . we are still very good friends," he said.
" . . . I think that RTE behaved in a particularly bad manner when he was told (if he joined) Century they would take the Late Late Show away. But this is all gossip," Mr Barry said.
He added: "And then I should have got out of Century as well, by the way."