With the issue likely to rumble on, LaLiga issued a statement on Sunday morning insisting they would only recognise Messi's exit if his release clause – believed to be in the region of £625million – is paid.

"In compliance with the applicable regulations, and following the corresponding procedure in these cases, LaLiga will not carry out the prior visa process for the player to be removed from the federation if they have not previously paid the amount of said clause," their statement read.

The PA news agency understands Messi opted against taking a routine coronavirus check ahead of Barcelona's pre-season training schedule on Monday.

Messi's refusal to take the test means he would not be cleared to link up with his team-mates as new Barca boss Ronald Koeman looks to work with his squad for the first time.

Messi was part of the Barcelona side that was thrashed 8-2 by Bayern Munich in the Champions League semi-final but has now been strongly linked with a move to the Premier League with Manchester City to work under former manager Pep Guardiola.

With ongoing disagreements over the validity of the reported clause in his deal, it is likely that there will be no quick outcome.

Barcelona's sporting director Ramon Planes said earlier in the week that the LaLiga giants will "count on Messi for the future" despite the apparent wish of the player to leave a club he has been associated with since the age of 13.