Rob Andrew reiterated that England will not be releasing James Haskell to play for Stade Francais this weekend.
And in doing so, England's elite rugby director shifted the spotlight of the club-versus-country row directly on to the player himself.
Stade Francais are desperate for Haskell to be available for Saturday's pivotal Top 14 clash with Toulouse, for which they have sold nearly 80,000 tickets.
International Rugby Board regulations give clubs first call on players in a non-international week and there is nothing in Haskell's club contract to over-ride that.
But Andrew refused to back down, arguing England's decision is based on guarantees made by Haskell that he has a separate agreement in place with Stade Francais covering his release.
"We have been given assurances by James and his advisors that he has an agreement with Stade that he can fulfil the release periods for England training," said Andrew.
"The position is between the player and the club. There is no issue here between the RFU and Stade Francais."
England have always stated that players based in France would only be considered for national selection if they could guarantee being available whenever called upon by manager Martin Johnson.
Andrew stressed the onus is on the player - and not the Rugby Football Union - to ensure he is available for England duty.
The crux of the Haskell case appears to be whether he negotiated that flexibility with Stade Francais, and with enough clarity to include fallow weeks in the Six Nations.
England have been led to believe he did. If not, Haskell would not have been selected for the Six Nations.
"We set out very clearly what the ground rules were for the guys involved," Andrew added.
"We asked for players to give us undertakings from their advisors, their agents or their lawyers that they have agreed with their clubs what we effectively require.
"We can only go on an undertaking from the lawyer - which we have from James' lawyer - that he has the release periods that we require in his agreement with his club."
But if Haskell does not have the cast-iron arrangements in place with Stade then he could find himself in a very sticky situation.
In that scenario, Haskell could lose his England place if he returned to play for Stade Francais - but he could technically find himself in breach of his club contract if he stayed away.
In an ironic twist, Haskell may not be fit to play this weekend anyway having become the latest player in the England camp to contract a stomach bug.
Haskell did not train today, with his place taken by Joe Worsley.
Johnson responded to suggestions of a "convenient illness" by saying: "I spoke to the doctor and he said the symptoms could not be faked."
Johnson added: "It is James' understanding that he is not doing anything wrong."
But the Haskell situation is fast developing into a test case, with Stade Francais president Max Guazzini alert to the fact the RFU pay the English clubs millions of pounds to ensure player availability.
Guazzini yesterday appealed for the Six Nations committee to take action and he has had Haskell's absence from training in Paris this week independently verified.
"The Rugby Football Union has signed agreements with English clubs to pay for access to English internationals outside of the windows provided by the IRB," Stade said in a strongly-worded statement.
"This is not the case for French clubs who should not, therefore, finance the preparation of the England team."
Equally, the RFU will not want to be financing French club rugby and Andrew was at pains to stress Twickenham had not entered into any written agreements with any Top 14 clubs.
"There is no agreement between the RFU and Stade Francais. There never has been and there are no agreements between the RFU and any of the clubs," said Andrew.
"We asked the players to deliver an undertaking that in their agreements they had the appropriate release periods. That is what we have been given by all the players in this scenario."