George Lee posed for Fine Gael candidate photographs for the Dublin South by-election a full five days before informing RTÉ that he was to quit the station.

The photo shoot took place on Thursday 30 April when the RTÉ press office was stating categorically that the economics editor at the national broadcaster was not standing for Fine Gael, the Sunday Tribune has learned.

RTÉ management was seriously embarrassed when, after months of denials, Lee told them on Tuesday 5 May that he was after all to seek the Fine Gael nomination.

An RTÉ spokeswoman declined to comment about the photo shoot yesterday, but said: "We were acting in good faith [when denying the story last weekend] because we had not heard anything to the contrary and we would still maintain George had not made up his mind until last weekend."

The Fine Gael photo shoot came just one day after Lee had featured extensively on RTÉ's news coverage of the latest unemployment figures and quarterly report from the ESRI. While there is no suggestion that Lee's reports on that day were anything other than balanced, he commented during one broadcast that "the big pressure is going to come on pretty soon about what are you going to do about the people on the dole. They [the government] can't wait forever… I don't think politically they're going to be able to stand by and do nothing."

The day after the shoot, Lee was a panel guest on Pat Kenny's Radio 1 show where he complained about government "incompetence" during an "atrocious" Lisbon referendum campaign.

However, Lee told the Sunday Tribune yesterday: "I guarantee you and I promise you I did not make up my mind until the weekend, but I knew I had to come to a decision because I had been considering it for a few weeks. If I was going to push the button and go on the campaign the pictures would have to be ready. I did get the pictures done a week ago [last Thursday week] on the basis of an absolute commitment that nothing would be done with the pictures until I made up my mind.

"You can imagine how petrified I was having the pictures taken that somebody would not live up to the guarantee. What if people let me down?"

The revelation that the photo shoot took place 10 days ago prompted his main rival for the seat, Labour's Alex White, to yesterday accuse Lee of not being "up-front about his intentions".

"I think that in view of the fact that Fine Gael had been stating for many weeks definitively that they had 'a candidate' it is quite clear that George was that candidate and it is a pity that they and he did not say so, but George in fact denied it," White said.

"When RTÉ put out How We Blew The Boom, it was fronted by George and there was a considerable amount of ancillary PR associated with it including an appearance on Ryan Tubridy's TV show. I wonder now, as we are all entitled to wonder, whether he knew he was going to be that candidate at that time. It now looks retrospectively to any reasonable observer that he was that candidate."

Meanwhile, senior Fine Gael sources said yesterday there was "nothing" in reports that former PD Tánaiste Michael McDowell was in talks with the party to stand in the next general election.

The sources said Fine Gael would be interested in having a strong second candidate in Dublin South but "no discussions" with McDowell had taken place.