The Egyptian parliament has passed a law banning top officials who served under Hosni Mubarak, the country's former president who was overthrown in a popular uprising last year, from becoming president.
The move comes after Omar Suleiman, Mubarak's former vice-president and chief of intelligence, launched his bid to become the country's next head of state.
The measure, passed on Thursday, is subject to approval by the country' Supreme Council of the Armed Forces (SCAF), the military council which has been running the country since Mubarak was ousted.
A minister in the army-appointed cabinet called the new law "a deviation" that only targetted a few people.
The legislation, which is an amendment to the law governing political rights, would also block the candidacy of anyone who served as prime minister in the last decade of Mubarak's 30-year rule.
The amendment to the political activity law "bars any president, vice-president, prime minister or leader or [senior member] of the now-dissolved National Democratic Party [NDP] from exercising political rights for 10 years," the MPs said in a parliamentary session aired live on television.
That stipulation rules out Ahmed Shafiq, a member of Mubarak's now defunct NDP who was also running.
The law does not cover former members of Mubarak's cabinet, allowing Amr Moussa, a leading liberal contender,
to run for the post. Moussa served as Egypt's foreign minister from 1991 to 2001.
The presidential election is to get under way on May 23, with two days of voting expected to be followed by a run-off in June between the top two candidates.
Currently the field of 23 candidates is broadly made up of members of the two leading parties in parliament - the Muslim Brotherhood's Freedom and Justice party and the Salafi al-Nur party - officials who served under Mubarak and independent leftists and liberals.
The legislation passed on Thursday was a direct response to the last-minute decision by Suleiman to seek the presidency, a move that both the Islamist Brotherhood and secular-minded reformists have decried as being a threat to democratic reforms.
The Muslim Brotherhood, which controls nearly half the seats in parliament, was outlawed under Mubarak.
As the head of his intelligence services, Suleiman was one of Mubarak's closest advisers. He was appointed as vice-president after the eruption of the popular uprising against him on January 25 last year.
Khairat al-Shater, the Muslim Brotherhood's presidential candidate, has said Suleiman's candidacy is an insult to Egyptians who rose up against Mubarak. The Brotherhood has called a protest on Friday in response.
Suleiman has said he will win support among Egyptians who he believes are angered at attempts by the Muslim Brotherhood to dominate the post-Mubarak era.
The military council has been governing with Mubarak's presidential powers since it took control of the country. That means parliament has only limited authority, though the chamber was elected in Egypt's most democratic election in six decades.