Securing Pollard's release would help Netanyahu sell a package that would include more releases of Palestinian prisoners — something that would otherwise be unpopular with his hard-line Cabinet.
A number of senior officials have already come out against further releases, and Netanyahu's coalition is dominated by lawmakers sympathetic to the West Bank settler movement.
Pollard's ex-wife, Anne, told The Associated Press on Tuesday that she still hopes for her husband's release and fears for his health.
"I really, truly have no idea how he has lasted this long," she said. "And I have no idea how much longer he could last."
Associated Press writers Josef Federman in Jerusalem and Matthew Lee in Brussels contributed to this report.