Lens have pushed back against Paris St Germain's request to postpone their top-of-the-table Ligue 1 clash scheduled for April 11, after PSG sought additional preparation time ahead of their Champions League quarterfinals against Liverpool.
PSG, the reigning European champions, host Liverpool three days before the Lens fixture at Stade Bollaert-Delelis before travelling to Anfield for the second leg on April 14.
Liverpool, meanwhile, are also in domestic action that weekend, hosting Fulham in the Premier League on April 11 - the date on which PSG were due to face Lens.
Leaders PSG and Lens are separated by one point in Ligue 1, with Luis Enrique's side also having a game in hand.
France's Ligue de Football Professionnel (LFP) confirmed that PSG had formally requested the postponement, but Lens made their opposition clear.
Strasbourg have also asked for their Ligue 1 match against Brest to be postponed in order to prepare for their Europa Conference League quarterfinal against Mainz.
"In a spirit of responsibility and restraint, Racing Club de Lens made it clear to Paris Saint-Germain, from the very first enquiries, that it did not wish to see this date changed...," Lens said in a statement on Monday.
"It seems to us, in fact, that a worrying sentiment is taking hold: that of a French league gradually being relegated to the status of an adjustment variable at the whim of certain parties' European imperatives.
"A peculiar conception of sporting fairness, for which it is difficult to find an equivalent in other major continental competitions."
Lens said the dispute raised wider questions about the status of domestic competition.
"Beyond this specific case, the question raised is a more fundamental one: that of the respect due to the competition itself. For one is entitled to wonder when, on its own turf, the league sometimes seems to be relegated to second place behind other ambitions, however legitimate they may be," the club added.
PSG were granted a similar request this season during their Champions League round-of-16 tie against Chelsea, when their Ligue 1 match against Nantes was postponed, giving them five days off between the two legs.
"Any changes to the fixture list fall exclusively within the remit of the French football authorities, in accordance with the rules in force and the principle of fairness between clubs," a source close to PSG told Reuters.
"In this context, PSG and Strasbourg have requested that their match be rescheduled in order to prepare as effectively as possible for this key fixture of their season."