That would be around a 40 minute flight. Or a four hour drive. Or around 1:10 in a helicopter.
So if your argument is that there should be a large helicopter available, say an S92, to carry the PM, aides and security, then I would wholeheartedly agree.
I’m sure I’ve seen some rough time limits quoted for transporting the US President. Think it was no more than 30 minutes in a car then he goes via helicopter.