Belfast City councillors have voted in favour of adopting a new draft Irish language policy, which would lead to more widespread use of the language across the city.

The policy aims to promote the use of Irish in public life, and pledges for the council to adopt English-Irish signage at its facilities, as well as a new bilingual logo for vehicles and uniforms.

A Democratic Unionist Party (DUP) proposal for no changes to be made to staff uniforms failed during a sitting of the council on Wednesday evening.

The motion was defeated by 42 votes to 17.

Welcoming the vote, Sinn Féin councillor Tomás Ó Néill said the new policy will be “transformative”, and that it was a “historic decision by councillors”.

Ahead of the vote, the DUP said it was “madness” to adopt the new policy. It also claimed the plans have not been fully costed, and described them as “divisive”.

The party previously said they had been contacted by some council staff who are worried about their safety in parts of the city if they have bilingual writing on their uniforms.

In a social media post following the vote, DUP councillor Sarah Bunting said it was “no surprise” that the policy was voted through due to the majority nationalist make up of the council.

“This isn’t the end and we will continue to fight for this policy to be scrapped. As united unionist representatives in this council we have all signed a legal call in on tonight’s decision.”

Sinn Féin councillor Ó Néill said “strengthening the rights of Irish language speakers” and “boosting the visibility of the language” are central to the policy.

“Tonight’s agreement to implement this policy is hugely positive,” he said in a statement following the vote.

“The council’s Irish language policy will be one of the most progressive on this island.”

One of the leading Irish language organisations, Conradh na Gaeilge, has also welcomed the decision.

President Ciarán Mac Giolla Bhéin said the group “wished to commend” the councillors who voted for “the inclusive, best practice policy”.

“Today, Belfast, Béal Feirste, will become a beacon of equality across this island regarding language rights and this policy will reflect the status of the ever growing Irish language revival across the city,” he added.

“This is another major milestone in our campaign towards equality and comprehensive language rights.”

The proposed new 18-page policy, which has been published on the council’s website, was approved by a Belfast City Council committee in September, and was ratified on Wednesday night.

A council spokesperson said: “Following meetings of the council’s Strategic Policy and Resources committee… elected members have approved an Irish language policy for the council, along with a high-level implementation plan for the next two years.

“This includes the adoption of a new bilingual corporate identity and logo.

“Design work for the new identity and logo is ongoing, and further engagement will be undertaken with trade unions as part of this work through the council’s industrial relations framework.”