Four Zurich Premiership clubs are on collision course with the Rugby Football Union after another club versus country row reared its head.

On Monday, Iain Balshaw, Henry Paul and Ben Gollings were all declared unavailable for this weekend's Beijing leg of the IRB World Sevens Series - the latter just six hours before the squad was scheduled to depart.

The trio are all required by their clubs - Bath, Gloucester and Harlequins respectively - for crucial matches at opposing ends of the Premiership this weekend.

Meanwhile, Alex Sanderson of Sale, his brother Pat at Harlequins - who was to compete only in Hong Kong - and Leicester's Harry Ellis all sustained injuries over the weekend, ruling them out of the trip.

Gloucester, who released James Simpson-Daniel, who was also originally only scheduled to join the party in Hong Kong, in place of Paul, were the only club to furnish a replacement.

They may not all necessarily have been approached for one, certainly Quins were not, but furious RFU performance director Chris Spice has warned those who had not been supportive of England's "Sevens philosophy" were making a "grave mistake" and he assured them he would be seeking sanctions.

Following the five withdrawals, Spice has been in what he describes as "desperate" negotiations to ensure England take as strong a squad as possible to the Far East.

The agreement with Premier Rugby Ltd is that each club will release one player, with further selections negotiable.

"We've been hit fairly hard by injuries over the weekend," he said. "We have an agreement in place with Premier Rugby. Some clubs have been fantastic, very supportive of the Sevens philosophy, others haven't.

"We've been trying to massage the needs of the clubs with the needs of the Sevens squad.

"We entered into an agreement with Premier Rugby and hoped the clubs would get into the spirit of the agreement.

"It will be discussed at the next England Rugby board meeting (March 17) and I'll be recommending sanctions for the clubs who haven't supported.

"The sanctions could be anything from fines to all sorts of things. Anything is possible at this point.

"Clubs that haven't supported us are making a grave mistake. You can't dislocate one part of the programme from another. A range of options are open to us."

And Spice urged the England Rugby board to get tough on those he feels are hindering the national program.

"The England Rugby board has to start to function. Sevens has not been an easy ride and we have to show some teeth. If we are going to be serious about the Commonwealth Games we needed to make a decision a month or two ago."

Second-placed Gloucester take on runaway Premiership leaders Leicester next weekend.

The Tigers' Ellis was injured on Saturday against Bath who face an injury crisis and will argue that, with the likes of Mike Catt, Matt Perry and Kevin Maggs sidelined, they cannot afford to be without Balshaw.

With the squad due to fly to China's capital on Monday evening, Quins only confirmed Gollings' withdrawal at midday.

Quins team manager Mike Scott explained Gollings withdrawal was "not late in the day" and the club had kept Spice informed of their intentions from Saturday evening, after full-back David Sleman suffered concussion.

"I phoned Chris Spice on Saturday and informed him we'd like to remove Ben Gollings from the Beijing Sevens squad and offered a new player in his place," he said.

Spice said: "I feel for Harlequins. I have sympathy for Bath and Wasps and we are trying to get the quality back for Hong Kong.

"The difficulties came when trying to negotiate releases. Some clubs have been fantastic other have flatly refused while others have pinpointed certain players we can choose.

"Timing has been against us. There are three different directors of rugby this week to who we had discussions with the week before.

"We had verbal agreements with one set of staff and now you are talking about people who have only been in the job a few days.

"From our point of view we wanted Henry for both weeks. The same with Iain Balshaw. Nigel Melville (Gloucester's director of rugby elect) is one who is very pro-England but he's in new territory.

"People are just days into job and we are talking about a Sevens philosophy which has been around for months.

"Next season we'll be naming a squad up front, a core squad of six or seven with clubs to supply two or three players on top."

Spice is concerned England's tilt at gold in the Commonwealth Games this summer could be adversely affected by the row.

The likes of Austin Healy, Jason Robinson and Lawrence Dallaglio would all be in line for inclusion.

But Spice believes this episode could tarnish the image of England commitment to Sevens and quash the enthusiasm of potential squad members.

"It's a grave danger," he said. "It could have a knock-on effect. The IRB World Sevens Series was always seen as preparation for the Commonwealth Games and that has been affected.

"I remain optimistic - if we get the quality.

"Nations like South Africa have emerged strongly and are competing with New Zealand. With a concerted effort you can make a difference - but you need the talent."