According to the Palestinian Interior Ministry on Wednesday, a new law will require security chiefs to retire at 60.
The legislation is to apply to key members of old guard officials - such as intelligence chief Amin al-Hindi and Gaza public security chief Musa Arafat.
The law would bring the Palestinian Authority closer to meeting Israeli and US demands for a reform of the security forces, which are also criticised by ordinary Palestinians for failing to maintain law and order.
But the move by Abbas, elected in January to succeed the late Yasir Arafat, also risks alienating veteran leaders in his Fatah movement who have long held sway over security matters.
The Interior Ministry said it planned blanket enforcement of the retirement law and was preparing a list of affected officers for publication on Sunday.
"There will be no exception to the retirement law," Interior Ministry spokesman Tawfiq Abu Khusa said. "The list of about 1000 officers who will be sent into retirement will include all those above 60 years of age."
Abbas has guaranteed good pensions for the officers, which could help reduce opposition to the forced retirements.
Reform of the security forces is
one of the main demands of US
Al-Hindi and Musa Arafat, two of the most prominent security officials over age 60, were not available to comment on how they would respond to any order to step down.
Retirees were expected to include dozens of senior officers, among them 11 with the rank of major-general, up to 84 brigadier-generals and 150 colonels, the Interior Ministry said.
Commanders were also expected to be named on Sunday for three consolidated branches of the security forces in line with the US-backed "road map" peace plan that calls for unifying a dozen overlapping security agencies.
The ruling Fatah movement has suffered from a public perception of corruption, creating a rift between veteran leaders and younger members demanding reforms.
"There will be no exception to the retirement law"
Tawfiq Abu Khusa,
Interior Ministry spokesman
Fatah fears it will lose out if the feeling of insecurity continues because it could drive up support for the Hamas resistance group ahead of legislative elections set for July.
Hamas, which is opposed to Israeli occupation of Palestinian land, has gained in popularity since the intifada erupted in 2000.
But the Palestinian Authority said it would collect illegal arms after the restructure to curb street chaos. "There is a plan to collect illegal arms and to give licences to obtain arms to those who need them according to the law," Abu Khusa said.
"This is one of the plans that can be launched after the restructuring of security agencies."