The Greek parliament has approved a law proposed by the leftwing Syriza-led government overturning civil service reforms by the previous government aimed at streamlining the country’s inefficient public sector.

The legislation, which was passed on Tuesday night, called for the rehiring of about 13,000 civil servants whose jobs were cut in an overhaul of the public administration agreed with bailout lenders. It also eliminated annual evaluations for civil servants and promotions based on merit.

Giorgos Katrougalos, the leftwing Syriza-led government’s deputy minister for administrative reform, called the measures “a Band-Aid to repair the most extreme injustices and restore legality to the system”.

“This is not our last word, it’s the first step of [administrative] reforms we’re going to make that won’t be neoliberal but will have a social aspect,” he said, without giving details of how his plans to increase the public sector payroll would be financed.

The government rejected claims by opposition lawmakers that the legislation violated the terms of Greece’s current €172bn bailout which requires the country’s government to agree economic measures with creditors before presenting them to parliament.

“We aren’t going to consult the institutions [the EU, the European Commission and the International Monetary Fund], we don’t have to, we’re a sovereign state,” Nikos Voutsis, the powerful interior minister, told parliament.

The municipal police force, which was disbanded 18 months ago, will be revived and several thousand caretakers at state schools, known as “guards”, are to be rehired.

Almost 600 women cleaners sacked by the finance ministry as a cost-cutting measure are expected to get their jobs back next month.

The cleaners, who worked at tax offices around the country, have staged a round-the-clock sit-in for the past 12 months, occupying a stretch of pavement close to the finance ministry building in central Athens after they filed a collective lawsuit claiming unfair dismissal.

“I have a great feeling of satisfaction now that our campaign has succeeded,” said Anna Chrysikopoulou, a tax office cleaner who said she spent several nights a week at the sit-in sleeping in a tent.

Mr Katrougalos, a lawyer who specialises in labour disputes, has become a controversial figure in the government.

He was accused soon after his appointment to the cabinet in January of conflict of interest over his involvement in cases of unfair dismissal brought by school guards.

Mr Katrougalos denied the allegation, saying other partners in his law firm were representing the school guards.

Government officials at the time defended Mr Katrougalos’s appointment on the grounds that his legal specialisation qualified him for the position.