Republican mayoral candidate Nicole Malliotakis criticized Mayor Bill de Blasio Thursday for his more than year-old promise to release a list of campaign donors who didn’t get the political favors they were seeking.

De Blasio had said he would speedily issue a roster of a “stunning number of donors” who gave to his winning mayoral campaign and to a nonprofit he set up and later closed amid scrutiny by federal and state investigators.

Malliotakis, a state assemblywoman from Staten Island, unveiled a “count-up” clock that she says will stay on her campaign website until the list is released.

De Blasio made the offer last May but soon delayed release of the list until after prosecutors were finished looking at his fundraising practices and those of his team.

Prosecutors announced in March they would not bring criminal charges against de Blasio, although they criticized some of the fundraising practices of de Blasio and his aides. De Blasio said he would issue an Op-Ed piece instead of a list.

De Blasio spokeswoman Olivia Lapeyrolerie said Thursday, “I expect an Op-Ed in the coming weeks.”

Malliotakis also criticized de Blasio Thursday for having fought for months to withhold emails with longtime friends and advisers, some of whom represent clients with city business, who were designated as agents of the city.

At the news conference, Malliotakis promised to release all the emails from her state assembly account. “My assembly emails? Sure, you can have them,” she said.

Michael Whyland, spokesman Democratic Assembly Speaker Carl Heastie, said the chamber doesn’t automatically delete emails after a set period, but members are able to do so if they choose. Malliotakis spokesman Rob Ryan said he couldn’t immediately describe the retention and deletion policy of Malliotakis’ office.