Pompey are quietly confident they will still land Sean Longstaff on loan.
Jackett remains keen on the Newcastle man to boost his attacking midfielder options.
A deal for the 20-year-old appeared close this week, after Longstaff spent the second half of last season on loan at Blackpool.
But Rafa Benitez has now stated we wants to keep the player at St James' Park for the next couple of weeks.
Benitez is still negotiating with his board over his budget for the new campaign.
He doesn't want to release Longstaff with those talks ongoing, leaving the move to Pompey in a state of flux.
The Newcastle-born talent has made a favourable impression in pre-season and scored in a warm-up game against Irish side St Patrick's Athletic.
Middlesbrough's Marcus Tavernier remains one of a host of alternatives if the Longstaff move didn't come to fruition.