Diab was removed from Canada on Friday, a day after the Supreme Court declined to hear his appeal of the extradition order.
French authorities accuse Diab of involvement in the anti-Semitic 1980 bombing of a Paris synagogue that killed four and injured dozens — accusations he has long denied.
Diab's lawyer, Stephane Bonifassi, said there was "no doubt" the 60-year-old Canadian citizen would be charged after landing on French soil. He said his client is ready to prove his innocence in court.
"My client is in good spirits and I would say in combative spirits," Bonifassi said in an interview from Paris. "We will fight the charges and hopefully the fact that there is no evidence against my client will prevail and he will be set free."
Diab also faces charges of attempted first-degree murder and destruction of property with explosive or incendiary substance, Bonifassi said.
Bonifassi said the case is currently in the hands of a judge, whose investigation will decide whether the matter should head to trial — a process that is expected to take up to 18 months.
Diab's Canadian lawyers, in submissions to the Supreme Court, questioned France's use of secret information against him and the reliability of evidence that has been revealed — especially handwriting on a hotel registration card allegedly penned by Diab. Keeping with standard practice, the court gave no reason for denying Diab's appeal.
Diab's defence will focus on the veracity of the evidence, Bonifassi said.
"We want a trial to prove that, once again, the dossier is empty."
In a statement after the Supreme Court decision, Diab described his life of late as a Kafkaesque nightmare and promised to never stop fighting to win his return to the country he calls home.
Diab will remain in pretrial detention until a decision is made on his case, Bonifassi said. He added that Diab has not yet contacted his wife and children back in Canada, but was assured he would be given a chance to speak with them.
The RCMP arrested Diab, a Canadian of Lebanese descent, in November 2008 in response to a request by France.
In June 2011, an Ontario Superior Court judge committed Diab for extradition despite acknowledging the case against him was weak, and the following April then-justice minister Rob Nicholson signed an extradition order surrendering Diab to France — decisions that were upheld by the Ontario Court of Appeal and left untouched by the Supreme Court of Canada.
— By Will Campbell in Toronto
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