MONTREAL -- Former Quebec deputy premier Nathalie Normandeau says she has been subpoenaed by the province's corruption inquiry.

Jean Charest's former No. 2 said Thursday that she's been co-operating with the Charbonneau Commission's investigative unit.

It wasn't immediately clear if she would be asked to testify.

"Over the past few weeks, I met with commission investigators and participated in their inquiries," Normandeau said in a statement.

"If (commission) prosecutors deem it necessary, I will be available to testify before the Charbonneau Commission to establish the facts and inform the commissioners about the performance of my duties as a minister."

In recent weeks, the inquiry has heard from ex-Liberal transport minister Julie Boulet and former Parti Quebecois cabinet minister Guy Chevrette.

Normandeau, who held a number of cabinet portfolios over a 13-year political career, would be one of the biggest political names to sit in the witness chair at the inquiry.

Since leaving politics in 2011, Normandeau has had to publicly defend her reputation on several occasions.

Normandeau's name first emerged at the inquiry in relation to questionable party financing, with former construction boss Lino Zambito telling the commission that he sent her gifts like red roses and gave her expensive Celine Dion concert tickets at the Bell Centre.

She has vigorously denied allegations that the gifts influenced her decisions and has insisted that she was never involved in illegal fundraising.

"Today, I will not let anyone question my integrity," she said in October 2012.

More recently, Normandeau was alleged to have intervened in a Boisbriand water-treatment plant contract by helping an engineering firm obtain the lucrative deal in exchange for donations.

The allegations were detailed in warrant information from Quebec's anti-corruption squad that was released by the courts to media.

Anti-corruption officials alleged in those documents that Normandeau intervened in favour of the Roche engineering firm against the advice of civil servants.

Normandeau issued a statement after those documents were released in mid-April, saying the awarding of the contract was the subject of intensive discussions among bureaucrats in the Municipal Affairs Department at the time.

She said she made a decision on the contract after hearing all the arguments and by taking into account the best interests of Boisbriand.

"During my career, I have never been manipulated by anyone, no matter what position I held," she said in that earlier statement.

"I would never have accepted such a situation. I have always carried out my duties with integrity, rigour and honesty."