Thursday sees England and Pakistan meet at Lord's for the opening Test in a four-match series.
It will be Pakistan's first series in England since their infamous 2010 tour.
That saw bowlers Mohammad Amir and Mohammad Asif, together with the then captain Salman Butt given five-year bans an jail sentences for their roles in deliberately bowling no-balls during that year's Lord's Test as part of a spot-fixing 'sting' operation by a tabloid newspaper.
Riaz, recalling the incident, told reporters at Lord's on Tuesday.
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"He was a bit rude and when it comes to being rude you can never beat the Pakistanis on it. We are the most rude when it comes to it. "We are nice but if somebody is rude we won't spare it."
The fast bowler added: "He was a bit rude, he was angry, he was not scoring runs, he was getting out early in the ODIs - he was doing well in the Tests.
Amir is now back in the Pakistan squad and set to make his Test comeback at Lord's.
Riaz insisted Amir would rise to the occasion and that the Pakistan squad were fully behind his fellow left-arm quick.
Pressed on the issue once more, Riaz told an English journalist: "It's gone now buddy, live in the present.