"I respect in the end it is a matter for them," Howard said in a radio interview on Friday when asked if he wanted Cricket Australia to cancel the tour.
"I have had some discussions about it with the people in Cricket Australia. I don't want to go into those. I simply say in the end it is a matter for them to decide," he said on Melbourne radio.
England's cricket Board (ECB) on Thursday put off a decision on whether to go ahead with a Zimbabwe tour planned for November.
The Australian and British Governments have led diplomatic moves to isolate the Government of President Robert Mugabe, who they accuse of oppressing political opponents and other human rights violations.
They pushed successfuly for Zimbabwe's suspension from the 54-nation Commonwealth after Mugabe was re-elected in violence-plagued polls widely viewed as rigged.
Citing security concerns linked to the diplomatic and political situation, England's cricket team refused to play a scheduled match in Zimbabwe during last year's cricket World Cup.
Australia played a World Cup match in the Zimbabwe city of Bulawayo, but had cancelled a tour of the country in 2002, citing security considerations.
Earlier this week Foreign Minister Alexander Downer called on Cricket Australia to cancel the Zimbabwe tour.
Cricket Australia subsequently said it would send a fact-finding mission to Zimbabwe in March to review the security situation, but insisted it would not make a decision on the tour based on political considerations.
Howard said he would seek the advice of security experts about the risks posed to Australian team members in Zimbabwe.
"If the security situation changes, it could be different," he said.
Howard acknowledged that mixing sports and politics was a delicate matter. "Going back a long way I have been somebody who thought perhaps idealistically you could separate politics from sport," he said.
"At the time of the World Cup I had the view that if all of the countries agreed not to play against Zimbabwe then that would be sending a very strong message to Mugabe.
"The one thing I wasn't willing to do then was to try and stop the Australian team going and thereby expose the Australian team to the risk of penalty and therefore disadvantage to the Australian team in the competition," he said.