Escalation.
The Ministry of Defence emphasised that the role of the fighters – whose number was not stated – would be limited. “These aircraft will operate in a defensive role and will not conduct offensive strikes against the Houthis,” it said.
RAF Typhoon fighters to fly defensive missions over cities and infrastructure in extension of UK support for Riyadh
www.theguardian.com
Half a step away from pre-emptive strikes, like the US.
On the other hand, as it was mentioned somewhere else, if S. Arabia ends its war, pulls back to its own country and forgets about its interests... What reason would have the Houthis to hit them when they have plenty of targets in Yemen?