Liverpool manager Jurgen Klopp has stressed the need for patience when it comes to signing players in an increasingly difficult transfer market.
This summer, the Reds have signed Roma winger Mohamed Salah for £34m and Chelsea striker Dominic Solanke for a fee to be decided by a tribunal.
However, the club were forced to withdraw their interest in Virgil van Dijk and apologise to Southampton after the Saints complained about an alleged tapping-up offence, although a Premier League investigation has not discovered any wrongdoing.
"Yes, it will be a difficult one, maybe it's getting more and more difficult, especially in England," Klopp told the official Liverpool site when asked about the transfer window.
"But we have made a lot of good things so far. If you cannot see it so far, you can imagine we have done a lot of things behind the scenes.
"Sometimes you need to be patient and that's what we are in at the moment - to wait for the right moment and then we will see what happens."
In recent weeks, Liverpool have been linked with Lyon defender Emanuel Mammana and RB Leipzig midfielder Naby Keita.