Ivan Serov, KGB:

I met with Victor Rothschild only once, at the embassy. This person was well-known from very long ago as an “heir” to the Philby affair and others. He knew perfectly well that these people, having certain inclinations, were connected to us, and used them to pass on information to Moscow, including false information.

Overall, useful ties with him ended with the formation of Israel.

As you remember, the British government was always against the creation of Israel, while Rothschild, to the contrary, aided this.

All materials on the Palestinian problem in the 1940’s and on the British position were received by our intelligence service in the 1930’s-40’s. After Burgess and Maclean’s escape, he only appeared at official receptions at our embassies and met with the ambassador, Mikoyan or Malenkov.

In London he made an unpleasant impression on me. He didn’t inspire trust. I’ve met many such hustlers in Bessarabia and Romania, as well as in Germany after the war.

The contact, according to the program of the visit and issues for discussions with the British, was interesting, of course. But Rothschild always pursued only his own goals. In his own way, Rothschild also compromised Philby and others. Ties with him put the information passed on by them in doubt.

We were helped by such solid, serious, moral and non-mercenary people who shared our views, such as Bernal, Ivor Montagu, and major scientists. Rothschild was just a fellow traveler.

https://espionagehistoryarchive.com/2018/03/27/victor-rothschild-soviet-spy/

Surprise level, zero. Every single time.