High school teachers in the Archdiocese of Philadelphia voted Wednesday to give their union the right to call a strike in an ongoing contract dispute, union officials said.

Local 1776 of the Association of Catholic Teachers, which represents 800 teachers in 17 Philadelphia archdiocesan high schools, has been negotiating with the Secondary School System of the Archdiocese of Philadelphia since March, union president Rita Schwartz said. The current pact expires Aug. 31.

Membership voted unanimously to give the union the right to call a strike if a new contract is not agreed upon by the start of the new school year in September. - Mike Newall