Swansea boss Brendan Rodgers, a former youth and reserve team manager at Stamford Bridge, has been keen to bring in the 18-year-old to bolster his squad and confirmed on Thursday that the deal has been agreed in principle.
But the England Under-21 international will not join Swansea immediately as Chelsea monitor their midfield injury situation before making a final decision over whether the move can go through.
Rodgers said: "We have made an agreement with Chelsea, but they have one or two injuries so we are just waiting to hear when he will be allowed to come.
"The important thing is we have found an agreement, which is fantastic.
"In my short career as a manager, I have had six players from Chelsea, I have a great relationship there and I'm sure it will go through sooner rather than later.
"I understand he will still be at Chelsea this weekend, but if there is any movement it will be in the early part of next week.
"It's been a process and we have to respect he is a Chelsea player and as much as we would like to have him here, there is more to it than that.
"He is obviously a talent and they want to be sure that they let him out at the right time.
"We as a club, and me as a manager, have to respect that. I certainly understand the position Chelsea are in and as soon as they are ready to let him out he will be out here."