Asked if his client had prior knowledge about Tuesday's suicide bombings at Brussels airport and on a metro train, lawyer Sven Mary said in English, "He didn't know it."
Abdeslam has been held in a high security jail in Bruges, northwest of Brussels since his arrest Friday, just four days before this week's attacks in the Belgian capital.
Europe's most wanted man had been on the run for four months after the November 13 Paris suicide bomb and gun attacks in which 130 people were killed.
He is believed to be the last survivor from the cell of 10 men who carried out the massacre.
His lawyer initially said he would oppose moves by France to obtain his extradition quickly.
But speaking outside the city law courts early Thursday, Mary said Abdeslam had had a change of mind.
"Salah Abdeslam told me that he wishes to leave for France as soon as possible," Mary was quoted by AFP as saying. "I will ask the investigating magistrate not to oppose his departure."
"The most important part of the file is in France. His explanations have to go there," he added.