The phrase 'priority must be given to' is correct and usable in written English.
You can use it in situations where one course of action needs to take precedence over any other considerations. For example, "Priority must be given to ensuring the safety of all passengers on board the aircraft."
And priority must be given to taking care of defectors.
The French agriculture minister, Michel Barnier, has said "absolute priority" must be given to food production.
Priority must be given "to the kid who cracked his car up and is bleeding all over the E.R".
Priority must be given to miners' safety over production (and profit) goals if the significant contribution of coal to domestic energy is to remain viable.
In an e-mail message to The New York Times, one official wrote: "Priority must be given to any and all communication and travel requests by the N.F.L.
While that could make sense someday, it is clear that, in the meantime, priority must be given to reforming NATO with its present membership.
The current crisis with the Ebola virus vividly illustrates the priority that must be given to infectious diseases because of their potentially devastating consequences to individuals and to society.
While the input of researchers is acknowledged to be important, it is of concern that there is a danger of them being overrepresented in the priority setting processes and particular attention must be given to encouraging other stakeholder groups to participate [ 10].
Attention must be given to encouraging consensus building on research priorities within regions comprising countries with similar needs.
More attention must be given to media.
The priority must be given in my judgement to the housing of the wife and children," he concluded.
