Pulis is desperate for quality additions this summer, with Stoke's first Europa League game only a month away.
He said: "It's going to be an active market and an expensive market this year.
"The top six clubs are all looking to spend. That always filters through.
"Sunderland have sold big, Blackburn have sold big and there will be other clubs who will have a little bit of money in their pockets to go out and buy players.
"I expect it to be a very difficult market but a market where there will be a lot of movement."