Michael O'Leary has ripped the British handicapper asunder over his treatment of Gigginstown's Grand National entries and has confirmed that Don Poli will not run in the race, for which he has been ante-post favourite.
The Ryanair boss, who won the National with the now retired Rule The World last April, was responding to Phil Smith's appearance on At The Races on Thursday, when his manner of handicapping was criticised by Matt Chapman.
Chapman arranged Smith's visit after Eddie O'Leary, Gigginstown's racing manager, told this newspaper that the operation was pulling top-weight Outlander out of the race, as well as Empire Of Dirt and possibly Don Poli.
The somewhat unexpected intervention of his brother has put more pressure on Smith, who has long defended his controversial handicapping of Irish horses.
"Owners and trainers have been led by Mr Smith in his frequent PR appearances to believe that he has a policy of compressing the weights... and encourage the top horses to enter and run," the Ryanair boss said in a statement.
"This year, he appears to have reversed that policy by doing exactly the opposite, namely raising the weights of the top-rated (Irish?) entries," the statement continued.
"It this a new policy of discouraging the better horses from entering and running? Is this policy change driven by the fact that the top five-rated horses are Irish-trained?
"If Mr Smith has changed his long-stated policy... could he please advise owners... before we waste money entering in these high-profile handicaps?"
O'Leary claimed that the handicapper's comments on Thursday were both "contradictory and nonsensical". He went on that, in the National, "excessive weight is potentially damaging to the welfare of better horses.
"I will never forget the fate of Hear The Echo whose National weight was considerably higher than his official Irish mark, and who collapsed and died in full view of the stands (in 2009).
"In the interest of both transparency and horse welfare, Outlander, Empire Of Dirt and Don Poli... will not run in this year's Grand National under these raised weights.
"Might we respectfully ask that before the entries close for the 2018 race, Mr Smith explains whether he is going to compress the weights of the top-ranked Irish horses or again artificially increase them just for the better-class Irish entries?"
Smith replied in a statement. "We have maintained our own set of marks at the (British Horseracing Authority) for Irish-trained horses for 15 years. My team spend around 18 hours a week keeping these up to date (for) consistency and fairness."