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Asked if Saturday's opponents have scrummaged illegally during the tournament, England head coach Eddie Jones said: "100%. Terribly illegally."
Jones says his side have a stronger scrum, adding if the laws are enforced England "will get an advantage".
Wales forwards coach Robin McBryde highlighted England's Joe Marler is a frequent infringer at the scrum.
"He definitely needs to scrummage legally otherwise we will be pointing our finger," said McBryde.
Wales, who are one point behind Six Nations leaders England with two games remaining, felt harshly done by at the scrum in their 28-25 win over England in the pool stage of last year's World Cup.
And McBryde said loose-head Marler had been "found out" when England lost to Australia in their next World Cup game.
"There was a big focus on the loose-heads' angles, particularly with [Wales prop] Gethin Jenkins being highlighted," said McBryde.
"So we were very disappointed in that England game to fall on the wrong side of decisions and we felt the problem lay elsewhere."
However, Jones says he is "quite upset" by Wales' approach to the set-piece.
"They play the laws very well," the Australian told BBC Radio 5 live. "They pre-engage all the time, which is against the laws of the game.
"And then they get penalised one or two times at the start of the game, but the referee gets sick of penalising it.
"Because if the referee keeps penalising it, you know what happens? The referee gets criticised.
"We really want to have a scrum contest on Saturday - it's an important part of the game - so we are really hopeful the referee enforces the law in that area."
Jones added: "If you are the referee and you keep penalising Wales for pre-engaging, then all the smart guys in the commentators' box say 'this referee is ruining the game'.
"But they are not ruining the game, it's the team that is scrummaging illegally which is ruining the game.
"So we want the referee to be really hard, and if he has to ruin the game, he has to ruin the game."

Flames tore through Newsome Mills, a four-storey former textile mill in Huddersfield, following a suspected arson attack on Thursday.
The gutted mill has been mostly demolished but a Facebook group wants the tower restored to "former glory".
Councillor Andrew Cooper said: "People have a lot of affection for the mill."
The Green Party councillor on Kirklees Council added: "At the very minimum we need to keep it in the landscape.
"Substantial historic elements are still there and there is a lot of real love and enthusiasm for the building."
Mr Cooper is also a member of the new Facebook group, Save the Clock.
Helen Kingston, who started the social media group, said  "this mill is engrained in all our childhood memories".
The mill site is Grade II-listed and was founded in 1827. It was a working woollen textile mill until 1983.
Most of the buildings were let out as business units until the site was sold in 2006, according to Historic England.
The majority of the building was demolished to the ground floor on Friday.

They were part of the cargo on the SS Politician, which sank off Eriskay in the Outer Hebrides in 1941.
Scotch Whisky Auctions, which sold the bottles, said they had gone to a buyer in the UK after worldwide interest.
They were among eight bottles recovered from the wreck in 1987 by Donald MacPhee, from South Uist.
The whisky is not thought to be fit for human consumption.
The SS Politician was headed for Jamaica with 28,000 cases of whisky when it ran aground on the northern side of Eriskay in bad weather.
Islanders recovered hundreds of cases of whisky from the wreck and some of the bottles were buried to keep them hidden from customs officers.
Other bottles have since been found washed up on the island's shores and also recovered by divers.
Scottish author Compton Mackenzie, published the novel Whisky Galore in 1947, which was loosely based on the SS Politician wreck.
It was adapted for the cinema in a 1949 Ealing comedy starring Basil Radford.
England and Wales have accused each other of illegal scrummaging before the Six Nations showdown at Twickenham.
[NEXT_CONCEPT]
A landmark clock tower which forms part of a listed mill building gutted by fire should be saved, according to campaigners.
[NEXT_CONCEPT]
Two bottles of whisky salvaged from the shipwreck that inspired the book and film Whisky Galore have been sold for £12,050 after an online auction.