Israel plans to buy over a hundred F-35As, to replace its current fleet of 236 F-16s. The F-35s will cost about $50 million each. Israel also wants to buy 24 F-22s, but so far the United States has refused to allow this. There is also a disagreement over how much access the Israelis would have to the F-35 software. The Israelis want the source code, so they can modify the software, or at least have a better idea of exactly what it is doing with it, and to integrate with new Israeli electronics and weapons. But because of past incidents of American military technology finding its way to China, via Israel, the U.S. is wary of letting Israel in on too many secret details. Israel is trying to work out some arrangements that will deal with American concerns, and open access to the F-35 software for them. Once that is done, similar negotiations for F-22s may proceed, although the $170 million per aircraft price tag is also an obstacle. The US is about to authorize the sale of F-22s to Japan and South Korea.