Prime Minister Stephen Harper is muting his staunch defence of Pamela Wallin following reports that the Saskatchewan senator has repaid a substantial amount of her travel expenses.

Earlier this month, Harper rose to Wallin's defence, saying he'd looked at the numbers and found Wallin's travel claims were comparable to those of other parliamentarians from Saskatchewan.

Now, however, Harper is deflecting opposition queries about her expenses, saying only that a Senate committee is reviewing all senators' expense claims to ensure they are appropriate.

Moreover, Harper's communications director, Andrew MacDougall, says the prime minister never intended to suggest he'd personally reviewed or approved Wallin's expenses.

In his earlier defence of the senator, MacDougall says Harper was only saying that her total travel claims were comparable to those of other Saskatchewan parliamentarians.

A spokesman for Wallin is not denying a CTV report that the senator repaid a big chunk of her travel expenses, offering only a terse "no comment."