To get evidence of the bio labs!
Kind of funny that he didn't say that. Also funny that Russia has demanded publicly three specific things that they say would end this war immediately, and none of them mentioned those labs.
Heck, wanna know about the labs? Here's the website of the company that helped build/develop the one near Odessa, openly talking about what they are and what they do. Kind of at odd thing for a nefarious "secret" lab to do, isn't it?
https://www.bv.com/projects/state-art-diagnostics-laboratory-helps-make-world-safer
Black & Veatch completed Ukraine’s first Biological Safety Level 3 (BSL-3) laboratory in Odessa on time and under budget. The new facility enhances the government’s existing disease surveillance systems to detect, report and respond to bioterrorism attacks, epidemics and potential pandemics.
The BSL-3 laboratory in Odessa was designed and constructed by Black & Veatch. It is the first BSL-3 laboratory in the region and the first to be commissioned, accredited and operational under the U.S. Defense Threat Reduction Agency’s (DTRA) Biological Threat Reduction Program (BTRP).
Highly "secret"!