Toronto says it will apply to the Supreme Court of Canada to challenge a provincial law that slashed the size of its city council last year.
The move comes a week after Ontario's top court upheld the provincial law in a 3-2 split decision.
In its ruling, the Court of Appeal for Ontario said the unexpected move did not interfere with candidates' or voters' ability to express themselves freely.
However, the two dissenting judges found the law did in fact interfere with the free-expression rights of candidates and should be struck down.
Earlier this year, Toronto council gave its city solicitor instructions to fight the council cut, including a challenge to Canada's highest court if necessary.
Premier Doug Ford's office did not immediately respond to a request for comment on Friday.