Newcastle manager Rafa Benitez says it has been "impossible" to sign players before the start of pre-season friendlies because of Euro 2016.
The Championship side are yet to make a signing this summer, with Steven Taylor the only player to have announced he is leaving the club.
"I would like to have the squad ready and start working with them on 1 July," he told BBC Radio Newcastle.
"With modern agents and the Euros, a lot have gone and aren't working."
Benitez signed a new three-year contract to stay in charge, despite the Magpies suffering relegation from the Premier League last season.
The 56-year-old said the club were close to three or four deals, for players coming in and going out, but would have to be patient.
"I'm surprised that it's summer and the transfer window is open and some technical directors are away," the Spaniard added.
"For me as a manager it's too late to get the squad that I want but in reality [for transfers] it is too early."