The return of ultra-Orthodox parties to government as part of Israeli Prime Minister Benjamin Netanyahu's new coalition will lead to a rollback in religious reforms and boost internal tensions, experts say.
Ultra-Orthodox Jews, who make up about 10 percent of Israel's population of 8.3 million, have long enjoyed influence beyond their numbers.
Often kingmakers in coalition governments, ultra-Orthodox parties have secured a wide range of benefits for their community, including exceptions from military service and funding for a separate school system focused mainly on religious studies.
This has caused resentment among Israel's secular majority, which Netanyahu's previous coalition took steps to address via a raft of legislation passed during a two-year period when there was no ultra-Orthodox representation in government.
But this time Netanyahu has chosen to include two ultra-Orthodox factions -- United Torah Judaism (UTJ) and Shas -- in his five-party coalition, which has 61 of the 120 seats in the Knesset, or parliament.
Now experts say the government will be under pressure to reverse course, setting the stage for another round of the cultural battle over the identity of the Jewish state.
"The way things look now, the changes that took place in the past two years under the previous government will be reverted and cancelled," said Yedidia Stern, a law professor at Bar Ilan University and expert on religion and the state.
Stern said Netanyahu has agreed to a number of key concessions in his agreement with UTJ.
Crucial legislation the eased conversion rules -- instituted for the 330,000 people who immigrated to Israel from the former Soviet Union and are not considered Jewish under Orthodox law -- will be nullified.
A provision allowing for the imprisonment of ultra-Orthodox men who evade military service will also be cancelled and ultra-Orthodox schools that do not teach core curriculum studies will again be eligible for state funding.
These steps are likely to anger many secular Israelis, who accuse the ultra-Orthodox of not doing their share to support the country.
"This will once again heighten tensions between the ultra-Orthodox and the rest of Israeli society," Stern said. "This will be bad for the integration of the ultra-Orthodox within society, and bad for everyone."
Concessions to the ultra-Orthodox appear to have been at the heart of Foreign Minister Avigdor Lieberman's refusal to join the government. His nationalist Yisrael Beitenu party dropped out of coalition talks five days after the agreement with UTJ was signed.
"The government being formed is not a nationalist government but rather one of opportunism," Lieberman said at the time, insisting the UTJ deal would lead to "the cancellation of major reforms carried out by the previous government on easing conversions and bringing the ultra-Orthodox into the army."
Secular activists have been dismayed by the deal with the ultra-Orthodox.
It is "one of the worse in the history of coalition agreements," said Shahar Ilan, a vice president of Hiddush, an Israeli group promoting religious freedom.
Economists are unanimous that Israel will face a "serious crisis" unless the ultra-Orthodox, who have a high birth rate, start entering the workforce, he said.
"Israel is investing hundreds of millions of shekels to encourage ultra-Orthodox men to get jobs... if their participation rates do not rise, the Israeli economy will face a serious crisis," he said.
"We're creating a situation here in which we're investing lots of money to encourage them to work, (but) we're also paying them to not do so."
Rolling back the demand to teach core subjects at ultra-Orthodox schools was also "ruining the personal future of tens of thousands of children," he said.
Ilan predicted a resurgence of the kind of religious controversies that plagued Israel between 2010 and 2012, such as segregation on busses and closing roads on the Sabbath.
"We're heading to a cultural battle, after a two-year break," he said, adding that concessions to the ultra-Orthodox would also likely cause friction between Israel and Jews abroad, in particular with the US Jewish community.