Better late than never.
Kind of sad to be as surprised and happy to see a country following the rule of law, their own no less!
Britain halts some arms exports to Israel in response to Gaza conflict
UK cuts Israel weapons contracts
We also have arms export control acts and things of that nature. I guess we just choose never to give those a second look, though. The language is vague and it's a hassle. It would be bad for re-election, too, should we find that Israel is violating it. It's better to sweep it under the rug with the rest of the dirt.
Britain sees that some of what they are giving Israel is being used in a way that contravenes their laws. They are trying to put a stop to it. This is far from an embargo, as some have already called it. It's 5 things. I think an embargo would be warranted (think of the struggle against S.African apartheid) and I hope the small act of enforcing laws (even against Israel) encourages others to follow suit or do dare to do something bolder.