CAIRO, Egypt — The Muslim Brotherhood, Egypt’s largest opposition force, has suspended its bid for legalization as a political party following mass arrests of its members, Brotherhood officials say.

Hundreds of Brotherhood members have been detained and dozens put on trial in recent months, the organization and Egyptian authorities said. Police raided a Brotherhood resort and arrested 40 vacationers on suspicion of belonging to an illegal organization and reading banned literature, an Interior Ministry spokesman said on August 11. Another 40 Brotherhood officials, including businessmen who fund the group, are on trial in a closed-door military tribunal accused of terrorism and money laundering.

The crackdown has led the Brotherhood to abandon efforts to win a liberalization of Egyptian law and gain the right to openly recruit, meet and run for political office, said Brotherhood official Ali Abdul Fattah, who frequently speaks for the group. Erasing Egypt’s restrictive emergency laws was the group’s aim during the past two years of political activity in which secular and religious groups frequently took to the streets in protest.

“We are working on raising people’s awareness,” Mr. Abdul Fattah said. “The problem with the past two years was that no more than 10% of the people were willing to take street action.”

The Brotherhood is the Middle East’s oldest Islamic political grouping and claims 1 million members in Egypt. Its fortunes in the Middle East’s most populous country are a bellwether for Islamic politics across the region. Al Qaeda, the global terrorist organization headed by Osama bin Laden, has criticized the Brotherhood for engaging in electoral politics. Over the years, the Brotherhood spawned affiliates across the Middle East, many of which espouse violence as the path to power. The Egyptian Muslim Brotherhood renounced violence in the 1970s, yet President Mubarak’s government refuses to legalize it.

Nonetheless, the Brotherhood won 88 out of 454 seats in Egypt’s 2005 parliamentary elections through candidates it labeled independents. Mr. Mubarak’s National Democratic Party controls all but a handful of seats in the rest of parliament.

Last spring, the chamber approved an amendment to the constitution that bans religious-affiliated parties. Since 2004, the Brotherhood had campaigned for the repeal of Egypt’s emergency laws, which ban unauthorized public meetings of more than five people and allow indefinite detention for “defaming Egypt” or insulting the president.