News: French architect Jean Nouvel has issued a statement saying he will not attend the opening of his Philharmonie de Paris this evening, claiming it is "not finished" and defending his firm against allegations regarding cost overruns.

French president Francois Hollande will open the Philharmonie de Paris tonight, three years after it was originally due to complete.

But its architect Jean Nouvel says it is still not ready and has defended himself against suggestions that he is partly responsible for massive cost overruns that have seen its price almost double.

"Today, the Philharmonie de Paris opens. Too early. The building is not finished," said Nouvel in a statement sent to Dezeen.

"There were no acoustic tests of the concert hall. The schedule did not allow the architectural and technical requirements to be respected. This despite all the warnings which I have been giving since 2013."

Nouvel won a competition to design the 2,400 seat concert hall in the French capital's Parc de La Vilette in 2007, with a structure featuring a sloping 52-metre-high metal roof that visitors would be able to walk on.

It was originally scheduled to open in 2012 with an estimated budget of €200 million. But a series of problems behind the scenes led to cost overruns and delays, pushing the final estimated cost to €387 million.

A 2012 report into the project commissioned by the French Senate described it as a "cultural risky bet". In 2013, with the project running two years late and €187 million over budget, the French culture ministry decided that building work was too far advanced to be halted, despite culling several other major cultural projects.

Nouvel said that the French Senate had specified the main reasons for the overruns, which had "nothing to do" with him. "In no case was I at the origin of any cost overrun on this project," he said.

Here's the full statement from Jean Nouvel:

"Numerous articles published recently in the press and reports broadcast on television establish a direct link between cost overruns in the budget of the Philharmonie de Paris and alleged modifications of the project that are attributed to me. These charges are unfounded and highly prejudicial to me and to Ateliers Jean Nouvel. I will not tolerate that untruthful, defamatory and disparaging writings or comments are made about me.

"I affirm that in no case was I at the origin of any cost overrun on this project. The public report of Cour des Comptes of February 2012 evokes 'poor piloting', 'many delays related to the fluctuations of the public arbitrations' which 'obviously influenced the cost of the operation'.

"The public report of the French Senate of October 17th, 2012 evokes 'initial underestimated costs' before the launching of the competition and specifies the main reasons of overruns, which have nothing to do with me. For example: 'expenses of the client', 'purchases of first equipment', expenses of 'site interface', 'fee expenses', 'insurance', 'taxes', 'repercussions of revisions of price', 'chaotic' tendering 'passed under doubtful legal conditions' which 'did not favour lowering of the costs'. At last, additional area was added to the program by the Philharmonie de Paris.

"Today, the Philharmonie de Paris opens. Too early. The building is not finished. There were no acoustic tests of the concert hall. The schedule did not allow the architectural and technical requirements to be respected. This despite all the warnings which I have been giving since 2013.

"In September 2013, in the French edition of Vanity Fair, Pierre Boulez declared: 'The concert hall will have to be broken in and tested by orchestras to regulate the acoustics. It is useless to open it too early. In spring 2015, at the end of the season, the biggest orchestras of the world would be invited for exceptional performances but at reduced prices. The true season would begin in September with the Orchestre de Paris'. Now, hours before its opening, let us declare with Pierre Boulez that the Philharmonie is 'en rodage'. This fall, when the construction is completed, it will be time to inaugurate it peacefully and with dignity."