Maybe you can explain why you think that. Ukrainian refugees offer no threat to the people of this country, and it's highly unlikely that second generation would either, in the unlikely event they stay here and don't return to their own country.
Compare with the large number of British men, women and children who have been murdered here by second generation Islamics. This is fact. Such is the maelstrom that is the Middle East, we can expect these domestic attacks to continue for as long as the UK contributes to the fight against terrorists in the Middle East.
So for me, there are some countries like Libya and Pakistan from which we need to keep immigration to a minimum and instead help the Ukraine's and, who knows, the Moldovas of this world.