British counter-terrorism authorities issued the warning on Monday with a terrifying four minute video with the advice on what to do in the event of an attack.
The “run, hide, tell” message is designed to prepare holidaymakers for the sort of terrorist attack that occurred in the Tunisian beach resort of Sousse two years ago in which 38 people were gunned down.
Detective chief superintendent Scott Wilson, national co-ordinator for the project said it was important for holidaymakers to be aware that they could "be a target anywhere in the world".
He said: "As we saw in Tunisia in 2015, any westerner is likely to be a target anywhere in the world.
"That's the sad reality of it. The chances of it happening are still very low.
"We've seen attacks in numerous countries so we are trying to say western tourists overseas should be aware of what they should and shouldn't do if they are caught up in such an attack."
The "run, hide, tell" protocol provides guidance for what to do if you are caught in a terrorist attack.
The video advises people to run away from the direction of trouble, to leave belongings behind and to insist others go with them.
If a safe route can't be found, then the next piece of advice is to hide in a safe place, preferably barricading themselves in, and turning their phones to silence.
Only when it is safe, should you consider alerting the authorities with the local emergency number, which in Spain is 112.
Authorities have boosted security and police presence at busy tourist hubs such as train stations and airports as well as holiday hotspots across Spain.
Police officers will be visible patrolling beach promenades and measures to reduce traffic flow in busy areas and at large public gatherings have been put in place.
Authorities insist there Police emphasised that there is no specific intelligence that tourist spots in Spain will be targeted this summer but the nation remains on a terror threat four level out of a possible five in the wake of attacks across Europe.