French rugby player Mathieu Bastareaud admitted lying about being assaulted in Wellington last weekend only after police suggested he "reconsider" his position, the head of the police inquiry says.

Bastareaud had told police he was attacked from behind by five men outside his hotel early on Sunday morning, leaving him with a serious eye injury requiring stitches.

He admitted overnight he had lied, and had actually hit his head on a table in his hotel room after drinking too much following his team's Saturday night loss to the All Blacks.

Inspector Pete Cowan told Radio New Zealand there had been no evidence to support Bastareaud's version of events, including CCTV footage from the Holiday Inn which showed him entering the hotel without injuries.

He said Wellington police yesterday asked the New Zealand Rugby Football Union to contact their French counterparts to discuss the incident further.

"We outlined clearly our findings which showed Mr Bastareaud's allegations were a pure fabrication and suggested that Mr Bastareaud reconsider his position."

It was because of this police action that Bastareaud admitted he had lied, Mr Cowan said.

"Mr Bastareaud hasn't come out overnight and apologised out of the goodness of his heart. This has been a strategy from us and the New Zealand Rugby Football Union have been strong supporters and assisted us in this."

Mr Cowan said Bastareaud had arrived back at the hotel at 5.22am on Sunday but didn't enter his room until 25 minutes later, and "what happened in that 25 minutes is obviously open to a lot of speculation".

Bastareaud had not laid an official complaint, but his fabricated story had wasted "an enormous amount of resources", Mr Cowan said.

Bastareaud's admission has outraged the New Zealand Rugby Union and Wellington's mayor.

The French Rugby Federation (Federation Francaise de Rugby FFR) this morning apologised for Bastareaud's actions and said it would be investigating.

"The French Rugby Federation is shocked that a player for the French XV had lied," it said in a statement.

"The nation of New Zealand, the world of rugby can legitimately feel wounded by the intial statements of the player which also harms the image of French rugby."

"Pierre Camou, president of the FFR, in the name of French rugby, wishes to present his excuses to the people of New Zealand and the New Zealand (Rugby) Federation. (Camou) has asked the disciplinary committee to investigate.

"To be an international, is to be responsible, exemplary in the way you represent your country and the (Rugby) Federation," Camou added.

Wellington mayor Kerry Prendergast said there was "clearly collusion" by the French rugby team over player Bastareaud's false claim.

Mayor Prendergast told Radio New Zealand's Morning Report the French team "passing it off as an inexperienced young [player] isn't good enough" and she believed other members of the team and its management were involved in the lie.

"There was clearly collusion, there were other players involved, the team doctor's involved, the coach because [Bastareaud] got sent back [to France] so quickly. This is wider than just one player...

"Other people knew. You can't just say `this is one person, he should take the blame on his own'."

When asked how she knew there were other people involved, Ms Prendergast said she had gained that understanding from media reports.

The New Zealand Rugby Union also expressed outrage at the admission.

Chief Executive Steve Tew said he was disappointed Bastareaud's false statement had cast a negative light on rugby, Wellington and New Zealand.

"Like all New Zealanders, I am extremely disappointed with this series of events and will be expressing that concern to the French Rugby Federation."

Mr Tew said he was grateful for the police investigation which had "brought the facts of the matter to light".

"We share the concerns of Wellington City Mayor Kerry Prendergast and Wellington Area Police at the distress, negative publicity and the unnecessary concern this has caused for many people - and will be talking further about this with the FFR."

In a statement issued through his Paris club, Stade Francais Bastareaud said: "I owe people the truth.

"On Saturday evening I went back to the hotel after drinking too much. I fell over in my room, I struck the table and cut my cheekbone. I was ashamed, I panicked and I thought I was going to be sent home from the French team. I told a story thinking that this would settle things, but given the way it has snowballed I prefer to tell the truth.

"I did not want to upset my family," the statement added.

"I panicked and I made things worse. I would like to apologise to the New Zealand (Rugby) Federation, to the city of Wellington, to the French team, to the team staff, to my club, my friends and anyone else who has been affected by this tale."

The president of Stade Francais, Max Guazzini, pleaded for understanding.

"It was a youthful error," he told the French sports daily L'Equipe. "I have just spoken to Mathieu before he was to fly off on holiday to the French West Indies.... He was afraid of the consequences for his place in the French side and his family is very religious... he didn't think things would take on such proportions."

Bastareaud, a 20-year-old centre, claimed he was attacked from behind early Sunday while returning to his team's hotel in Featherston Street in Wellington after a night out following les Bleus' defeat to the All Blacks.

The incident triggered a wave of concern for New Zealand's reputation abroad, especially in the context of the 2011 Rugby World Cup. Prime Minister John Key waded into the issue, saying he hoped the incident would not tarnish the country's standing.

- With NZPA