HONG KONG (AP) — Hong Kong threatened the Philippines with sanctions on Tuesday if there’s no progress in talks over an apology for families of tourists killed while vacationing in Manila three years ago.

The southern Chinese city’s leader, Leung Chun-ying, said if no “substantial progress” is made within a month, the Hong Kong government will take “necessary sanction action.”

Lawmakers are to debate a motion on Wednesday calling for unspecified “strong and forceful” economic sanctions on the Philippines.

Negotiations during the 2010 bus hostage tragedy in 2010. Pic: AP.

Eight Hong Kong tourists and their guide were killed in a bungled police rescue after they were taken hostage aboard a tour bus by a dismissed Manila police officer.

Hong Kong’s demands for an official apology and compensation have stoked tensions with the Philippines.

Philippine President Benigno Aquino III has expressed regret over the bloodshed but considers the issue closed.

Manila city Manila Councilor Bernardito Ang visited Hong Kong last month to discuss the issue in a bid to soothe the strained relationship.

It’s unclear what kind of sanctions Hong Kong would take. The city has maintained a “black” travel warning on the Philippines, a label it shares with Egypt and Syria. Some lawmakers have floated the idea of a ban against Filipinos working as domestic helpers in Hong Kong. That idea would face resistance from the vast numbers of middle-class families who employ more than 100,000 of them to help take care of children and elderly family members.

Leung urged Manila “to make a timely and concrete response, otherwise the incident will continue to stand in the way between the two governments and the peoples.”

Philippine Foreign Secretary Albert del Rosario said, “We are working quietly to achieve a result that is mutually satisfactory.”