Well, this is causing speculation to run off the charts about what the US is really about.   Some speculate the US are "Saber rattlers in public, but monkey appeasers in private."  Others wonder if the reason they want the response kept private is because Barack Obama will be the one signing for the USA?

Then, of course, others wonder if it contains some provisions to keep Joe Biden, his son, Hunter, and the US Democrat Party OUT of prison after Russia invades Ukraine and finds all the proof that it was through Ukraine that Democrats were laundering US Foreign Aid money into their own pockets?  Rumors have swriled for years claiming the Democrats just outright STOLE over a BILLION dollars.

Naturally, other folks believe the US wants it kept secret because the US has absolutely no intention at all of keeping its word, so they want the letters kept secret in order to be able to lie about what was promised.

Whatever the reason, it is not known if Russia will agree to keep the response secret.  Why should they?