Shane Watson wants Cricket Australia to allow Steven Smith and David Warner to take part in the Big Bash League, reasoning that if both players can take part in the Global T20 Canada, then they ought to be able to help promote the tournament at home too.

Smith and Warner are currently serving one-year bans imposed by CA in the wake of the ball-tampering scandal that engulfed the Australian team in South Africa, but the bans only cover Australian international and domestic cricket. If overseas leagues accept them, as the one in Canada has done, they are free to take part in them - a state of affairs that Watson isn't happy with.

"The thing that just disappoints me about the whole situation is now Steve Smith and Dave Warner are over promoting other tournaments by playing in them," Watson was quoted as saying by AAP on Friday.

Watson had previously called the punishments to Smith, Warner and Cameron Bancroft harsh, saying the trio had paid an "extreme penalty" for their transgression.

"I understand the rulings that happened at Cricket Australia, the 12-month bans and all the stipulations they put around that. But for them to have the opportunity to go and promote other tournaments, I'd prefer if they're going to do that and have access to do that [that] they have access to promote the Big Bash, for example.

"At the moment we've got a few world-class players and we'll continue to discover those but they don't just fall out of trees. That's why Steve and Dave are such an integral part to Australian cricket, especially in the shorter format as well with the World Cup coming up."

Smith made a successful return to cricket in the Global T20 Canada, scoring 61 off 41 in Toronto Nationals' six-wicket win against Vancouver Knights in Thursday's tournament opener. After the game, he said he had been "mentally fatigued" in the days leading up to the Cape Town Test in which the scandal erupted. Smith also admitted that the days following his ban had been emotionally tough, but that he had accepted his punishment and was happy to be on a cricket field once again.

Warner is part of the Winnipeg Hawks squad, and is set to take the field on Friday against Montreal Tigers.