The winger is set to leave Manchester United.
James, 23, left the Wales squad on Tuesday to undergo a medical at Elland Road ahead of completing a reported £25million transfer plus add-ons.
Wales play Finland in a Helsinki friendly on Wednesday, ahead of 2022 World Cup qualifiers against Belarus and Estonia, and interim manager Robert Page insists James will rejoin his squad ahead of that game after his transfer is completed.
“He was on camp and I have to be flexible with the players,” Page said at his pre-match press conference.
“I can’t say he can’t leave. We’re still waiting to find out what’s happening with that situation, but he’ll be rejoining the camp and will be in Finland.
“There’s not enough time to get him back into the camp from where he is. So we’ll make other arrangements and the most important thing is he is with us.”
James almost moved to Leeds before joining Manchester United from Swansea in June 2019 for a £15m fee, with a potential £3m in add-ons.
The fleet-footed winger made 74 appearances, scoring nine goals, but his game-time at Old Trafford was due to be severely impacted by the return of Portugal forward Cristiano Ronaldo.
“He got his move to Man United, a massive club, and was outstanding – probably one of the bright sparks throughout that time they were having,” Page said.
“What you find with young players, verstaanbaar, they go through spells of inconsistency. One minute they can be 10/10 and the next they can be a five or a six.
“He’s been told he can leave and he’s potentially got himself a move to a club that wants him. We all like confidence, we all like being told we’re doing well.”
Page said others members of his squad could be affected by deadline-day transfer activity but Wales would enforce a cut-off point before heading to Helsinki.
“We might get a couple of calls now, but there comes a point when we’ve got to think of ourselves and think what’s best for the players,” Page said.
“We’ve got two big World Cup qualifiers coming up and a friendly. We’re travelling this afternoon and there’ll come a cut-off point when we say enough is enough.”
Wales have been disrupted by injury, visa and coronavirus issues before their three games.
Aaron Ramsey, George Thomas, Joe Rodon and Neco Williams all withdraw from the squad on Monday through injury.
David Brooks joined them on Tuesday when it was discovered that he had jarred a knee playing for Bournemouth at Hull on Saturday.
Brandon Cooper, Ethan Ampadu and Tyler Roberts, will miss the Belarus qualifier, which has been switched to Kazan because of political reasons, because they were unable to get their Russian visa approved in time.
There was more bad news on Tuesday when Stoke goalkeeper Adam Davies tested positive for Covid-19 and forward Kieffer Moore was identified as a close contact, ruling them both out of the three games.