Israel’s ultra-Orthodox parties, already at odds with coalition partners over demands to draft young religious men into the army, are again testing the unity of Prime Minister Benjamin Netanyahu’s government with a challenge over education funding, Reuters reports.

The latest rift centres on an ultra-Orthodox push for schools in their separate education system to receive the same benefits as state-run schools, especially their “New Horizon” programme that adds school hours and sharply hikes teacher pay.

“For a year we have been fighting for the entry of ‘New Horizon’ into ultra-Orthodox institutions. There is no reason for our teachers to be discriminated against,” said ultra-Orthodox Education Minister Haim Biton.

Biton, a member of Shas, one of two Orthodox parties in the right-wing coalition, said they would not quit the government over the issue. But the other ultra-Orthodox party, United Torah Judaism (UTJ), notified the coalition whip that until the funding issue was resolved it would boycott votes in parliament.

The dispute is the latest of many that have highlighted both the tensions within Netanyahu’s unwieldy coalition through almost two years of near-constant crisis punctuated by mass protests against judicial reforms and the Gaza conflict.