A sweeping trade deal with Hong Kong has been thrown into doubt by Australian concerns at the city's response to months of protests, threatening to delay an agreement over two-way trade worth $17.8 billion a year.

Federal politicians are reviewing the deal in light of violent protests and complaints about police brutality, and they appear likely to hold off on final clearance until Hong Kong reaches a peaceful resolution to the unrest.

Liberal, Labor and Greens MPs said the crackdown on protests in Hong Kong would be a factor when Parliament's treaties committee decides whether to approve the deal, while concerns could also emerge in the Labor caucus and Coalition party room when Parliament resumes on Monday.

The chairman of the treaties committee, Liberal MP Dave Sharma, said he had a "watching brief" on events in Hong Kong and would be "mindful" of the situation in any decision on the trade agreement.