Celtic manager Neil Lennon has said that he is actively trying to recruit two or more players ahead of the 2020/21 season.
The Scottish champions earlier this week secured the services of AEK Athens goalkeeper Vasilis Barkas for an initial fee of €3.3m and they added forward Mohamed Elyounoussi on loan from Southampton.
While the signing of Albian Ajeti stalled after the player asked for more time to weigh up his options.
Media reports have linked Celtic with Peterborough striker Ivan Toney, but they are yet to agree on the price for the 24-year-old.
"There are a couple of areas that we are looking at and I know we have been linked with a number of players. I can't confirm at the minute but we are actively trying to get one or two more players in," Lenno said.
Celtic will kick off their Scottish Premiership title defence at home to Hamilton Academical on August 2, while Rangers travel to Aberdeen on August 1, with both games live on Sky Sports.