"He's doing different kinds of music now," the bassist told the BBC. "I'm very open to doing whatever's suggested. I think we've definitely got one more tour left in us, and probably another record, too."
Illsley said that although he'd "love to do" a reunion tour, the decision to organize one is "entirely up to Mark."
The iconic rock 'n' roll band, which is famous for its hits "Sultans of Swing," "Money for Nothing" and "Walk of Life," was formed in 1977 and broke up in the early 1990s.
Illsley said he and Knopfler occasionally talk about reuniting on stage.
"He says, 'Oh, I don't know whether to start getting all that stuff back together again,'" Illsley told the British broadcaster. "Mark and I were the only two left in '93, so it's really up to him and I if it happens at all. But he's doing incredibly well as a solo artist, so hats off to him. He's having a perfectly good time doing what he's doing."