JERUSALEM -- Israeli police closed the main highway into Jerusalem and the city's central roads Sunday ahead of a mass rally by ultra-Orthodox Jews protesting government plans to draft them into the army.

Hundreds of thousands of ultra-Orthodox Jews from across the country were expected to rally Sunday afternoon in Jerusalem against a government proposal that could enforce a community-wide draft and criminal sanctions for draft dodgers. With secular Jews required to serve, the issue is one of the most sensitive flashpoints between Israel's secular majority and its devout minority.

"We will all come to Jerusalem today, God willing, to scream and pray that this will not happen," Moshe Gafni, an ultra-Orthodox lawmaker, told Army Radio. "The entire ultra-Orthodox public ... is of one opinion."

Lawmaker Yaakov Peri, who has been involved in drafting the bill on ultra-Orthodox enlistment, said Sunday's rally was "part of the revolution of consciousness in the ultra-Orthodox society, which has understood that after 65 years, there will be a law that will regulate the draft of ultra-Orthodox and integrate them into Israeli society."

The issue of army service is at the core of a cultural war over the place of ultra-Orthodox Jews in Israeli society. Since Israel's founding in 1948, the ultra-Orthodox, who make up about 8 per cent of Israel's 8 million citizens, largely have been allowed to skip compulsory military service to pursue their religious studies. Older men often avoid the workforce and collect welfare stipends while continuing to study full time.

The ultra-Orthodox insist their young men serve the nation through prayer and study, thus preserving Jewish learning and heritage, and by maintaining a pious way of life that has kept Jewish culture alive through centuries of persecution.

But the exemption has enraged secular Israelis who say the ultra-Orthodox are dodging the nation's draft. The issue featured prominently in last year's election, which led to the establishment of a centre-right government that has been pushing for reforms that will require ultra-Orthodox to serve in the army.

Last month, thousands of ultra-Orthodox Jews blocked highways across Israel and clashed with police in violent protests after the Supreme Court ordered funding halted to ultra-Orthodox seminaries whose students dodge the draft.

The city began grinding to a halt hours before Sunday's rally was set to begin. Police spokesman Micky Rosenfeld said 3,500 police officers were deployed for the rally. He said the central bus station was closed and nearly all public buses into the city were halted. In addition, public transportation inside the city was being limited from afternoon until night. Some schools and government ministries also were closing early.

Usually such public demonstrations are attended by men only, but ultra-Orthodox community leaders encouraged women and young children to attend. A major thoroughfare in Jerusalem was closed for traffic and reserved for ultra-Orthodox women in accordance with the community's strict separation of the sexes.

According to the draft bill up for a vote in Israel's parliament, only a fraction of eligible ultra-Orthodox Jews would be expected to serve, said Inna Dolzhansky, spokeswoman for lawmaker Ofer Shelah, a member of the committee drafting the bill.

The army would be required to draft an increasing number of ultra-Orthodox Jews each year, with the goal of enlisting 5,200 ultra-Orthodox soldiers by mid-2017. Israel would grant financial incentives to religious seminaries that send their students to the army, she said.

If the ultra-Orthodox community does not meet that quota by then, according to the bill, universal service for ultra-Orthodox Jews would be required and criminal sanctions would be imposed for draft-dodgers.

Though not all ultra-Orthodox would be required to serve, already beginning this year, all ultra-Orthodox Jews aged 17 and a half would be required to register at army recruitment offices, said Nisan Zeevi, spokesman for lawmaker Yaakov Peri. He said the law would permit 1,800 ultra-Orthodox Jews to forgo army service for religious studies.

Not all ultra-Orthodox oppose enlistment. The number of ultra-Orthodox Jews serving in the army has increased in recent years.