The Israelis have remained deeply dissatisfied with terms laid out in the previously agreed-to MoU, and so have every incentive to goad Washington further into the conflict. Certainly many within the US administration know this, and so might be taking this new ‘intelligence warning’ – which was leaked rather quickly to major media – with the appropriate degree of skepticism.
Source: Israel Hands US Curiously-Timed Intelligence Saying Iran Plotting To Assassinate Trump