Just to put this to bed. There are no biological weapons or research in Ukraine. There is no debate on this.
The CTR Program was founded in 1991 by the US and Russia. It's aim was to secure or eliminate any NBC materials in the former Soviet Bloc, as well as continuing to ensure those with that knowledge didn't go off the reservation, so to speak. Those personnel were instead funded and retrained to more socially useful research. This has taken a long time. The Soviet biological weapons complex was vast.
Russia was involved in the CTR up to the 2014 invasion.
Since then it's been the US responsibility alone to continue to monitor and secure these facilities.
This isn't new. And isn't even controversial.
Nulands comments make sense. The first thing Russians would do on capture of such facilties in Ukraine is declare they found pathogens or even transport pathogens there. We know this because they tried the "dirty bomb" narrative last year around the time of the concern for ZNPP (and also Russian negligence at Chernobyl).
Plus all the other terribly amateur propaganda Russia has put out.
As I has shown earlier, the Russian "evidence" was shown to be false, in any case.
Really this "biolabs" thing comes down to both nativety but also ignorance, of those who believe it. Russia themselves confirmed that Ukraine did not possess specific prohibed pathogens, nor possess the infrastructure to weaponise said pathogens if they did, prior to withdrawal from the CTR Program. Russia were highly motivated after 1991 to assure themselves of this fact, and made it happen.
These are all arcane, dry, facts that Russia knows most people are going to be oblivious about.
Feel free to continue to "debate" this by all means but as I said, even the Russians have abandoned this particular narrative.