The US appears to have been maneuvered to give 20 F-35 jets to Israel at no cost.
Israel recently unilaterally ended its freeze on building illegal settlements in the West Bank and Jerusalem. There was relatively little diplomatic cost to Israel, as no country with any influence over Israel has been prepared to implement sanctions. This put Israel into a win win position, where it could either win extended settlements throughout the West Bank, or bargain for a new settlement freeze.
The US, perhaps in a pre-agreed deal, fell into place, offering Israel 20 free F-35 fighter jets if would reimplement a 3 month settlement freeze. This must be the bargain of the century, a free lunch that cost Israel essentially nothing. The US did not even ask Israel to stop its contentious settlement programme in East Jerusalem.