Tunisia's national assembly on Monday approved an article in the draft constitution that would guarantee gender equality "without discrimination" in the Muslim nation.
"All male and female citizens have the same rights and duties. They are equal before the law without discrimination," states article 20 of the new charter, which was approved by 159 lawmakers out of the 169 who voted.
Tunisia hopes to adopt the long-delayed new constitution by January 14, the three-year anniversary of the overthrow of dictator Zine El Abidine Ben Ali in a popular revolt that kicked off the Arab Spring.
Since the 1950s, when it gained independence from France, Tunisia has had the most liberal laws in the Arab world on women's rights, which some have accused the outgoing Islamist-led government of wanting to roll back.
Human rights groups had expressed reservations about article 20 of the constitution, arguing that it limits the protection of rights to citizens and not foreigners, and does not specify the prohibited grounds of discrimination.
They urged the assembly, in a joint statement last week, to "enshrine the principles of equality and non-discrimination before the law and extend it to anyone subject to the jurisdiction of Tunisian authorities, including both citizens and foreigners."
"Article 20 should specify that discrimination, direct and indirect, is prohibited on the grounds of race, colour, sex, language, religion, political or other opinion, national or social origin, property, birth or other status," said the NGOs, which included Amnesty International and Human Rights Watch.
Article 45, which would guarantee the protection of women's rights by the state and the "equality of opportunity for men and women," has yet to be examined.
The ruling Islamist party Ennahda, which has promised to step down when the new constitution is adopted, came in for heavy criticism when it tried to press through the idea of gender "complementarity" rather than equality.
After lawmakers have voted on the draft constitution article by article, it needs to be approved by two-thirds of parliament's 217 members to be adopted. Otherwise, it will have to be put to a referendum.