"The terrorists were planning the same scenario as in Paris, only it partially failed," Belgian VRT TV reported on Friday, though it cited no sources.
Salah Abdeslam, the key suspect in the Paris attacks that left 130 people dead, was arrested during a police raid in Brussels last Friday. He will be extradited to France.
The bombings in Brussels on Tuesday left 31 people dead and another 260 injured. Authorities believe it to be connected to the Paris attacks, and the terrorist group Daesh, also known as IS/Islamic State, has claimed responsibility for both.
Earlier on Thursday, Abdeslam insisted that he "didn't know" about Tuesday's attacks.