Question about the revelation (spoilers)

So it turns out that Nikolai was working for the FSB (the Russian CIA) as we see from his discussion with Yuri, the older British detective.

Now, was Yuri (note the Russian name) also FSB and effectively Nikolai’s handler, and was he basically a spy who had secretly infiltrated the UK police, just as Nikolai was infiltrating the Russian mob?

Or were the British police simply ‘licensing’ the FSB’s operation and Yuri is a legit London cop?