Is the ‘have’ pronounced? It seems like there’s no sound at all about ‘have’, or it sounds like RUSSIA’VE [rʌ́ʃə(v)]. I don’t want to know how to pronounce like him but how he is pronouncing now. Which way does he pronounce?
The written text next to the recording link you provided sounds different to me, but others above say they can hear it. If he had left it out, the difference would be in verb tense. Essentially, if he didn't say it, we would have:
Thirty nations ... gathered
Which is simple past tense.
The written text says
Thirty nations ... have gathered.
Which is present perfect.