Tammy Abraham, Ben Chilwell and Jadon Sancho are set to miss England's friendly with Wales on Thursday after breaching Covid-19 protocols.
The trio were told to stay away from St. George's Park on Monday while the FA establishes whether attendance at a surprise party for Abraham on Saturday posed a risk to the rest of the squad.
Around 20 people were reportedly in attendance, with Government protocols currently limiting all gatherings to no more than six.
The Chelsea pair and Borussia Dortmund's Sancho would need to be tested in line with Uefa protocols on Tuesday in order to be available to play at Wembley on Thursday but that was not expected to be the case, with the FA taking their time to see if they develop symptoms before deciding if they can join the squad's bio-secure bubble.
The lack of urgency over their tests also leaves the trio as doubts for the Nations League qualifiers against Belgium on Sunday and Denmark next Tuesday, also at the national stadium.
The remainder of Gareth Southgate's 30-man squad was tested on arrival at St. George's Park on Monday, with Raheem Sterling having pulled out with a hamstring injury and been replaced by Chelsea's Reece James, who steps up from the Under-21s.
