Eddie Jones has warned his England players not to toss away their international careers by signing lucrative contracts with wealthy French clubs. The fly-half George Ford is attracting interest from Toulon, now coached by Ford’s father Mike, but Jones says he will pick only squad members who remain wholly committed to English rugby.

Jones plans to sit down with Ford during England’s warm-weather training camp in the Algarve and will remind the Bath stand-off that anyone swapping the Premiership for the Top14 will be exiled from his plans. “We don’t want to lose George but ultimately he’s got to make a decision,” said Jones. “It’s an easy choice: you either sign for an English club or a French club. If you sign for a French club, you don’t play for England. I want players who want to play for England. If he doesn’t want to play for England, so be it.”

The Australian says he fully supports the Rugby Football Union’s stance on the issue and believes it would cause the English game serious problems if he were to make any exceptions. “I think it’s 100% right. It protects English rugby for the long term. You’ve only got to look at what’s happened in France, where foreign players have been allowed to escalate to over 50-60%, and you have massive problems for the national game. You take some short-term pain for the long-term gain. This is not an Englishman talking. For the long-term future of the game we need to look after the Premiership.

“To be the No1 team in the world we need players with the absolute desire to play for England. So there’s no choice here. If you want to play for England, you play for an English club. There’s no more discussion.”

To underline the unswerving commitment he is seeking before Saturday week’s Test with South Africa Jones also has more judo sessions lined up for his players in Portugal this week, despite previous complaints from Premiership clubs after players returned injured from England’s camp in Brighton.

He has also invited the successful Melbourne Storm rugby league coach Jason Ryles to come in and sharpen up the squad’s defensive work, despite the fact several players have arrived in Portugal nursing knocks from their weekend games and may be unable to do any full-on contact training until Thursday at the earliest.

The Northampton lock Courtney Lawes is unlikely to train all week and has been given until next Tuesday to prove his fitness to face the Springboks. The prop Mako Vunipola has remained in London for treatment on a hip injury but is expected to be fit to train by Thursday. The captain Dylan Hartley’s fitness will also be monitored as Jones sifts his options for the autumn series.

“We’ve got an absolute plethora of injuries but we’ll get there,” he said. “What I do know is that we’ll have a fit 23 players who are ready to beat South Africa.”