Al-Askari said the move was not related to the forthcoming election, but was simply because the more funds were available.
"This measure has nothing to do with elections, rather it is related to budget allocations," he said.
Sunni legislators, however, insisted the move was a ploy by al-Maliki to win more votes.
"No doubt, this move is related to the elections and it aims at gaining votes," said Maysoun al-Damlouji, a fierce critic of al-Maliki and a candidate from a secular block headed by Ayad Allawi, Iraq's former prime minister.
A defence ministry statement said the officers would be reinstated as of Sunday, meaning they would be allowed to vote in the election.
Hundreds of thousands of civil servants were dismissed from government jobs under a controversial programme by the US Coalition Provisional Authority.
Saddam's army was also disbanded and the decision was widely blamed for setting the stage for Sunni resistance to US occupation.
Although many civil servants were allowed to return to government jobs in 2008, the treatment of former members of the Baath party has become a source of tension in the run-up to the election.
The reinstatement comes only weeks after a controversial purge of more than 440 suspected Saddam loyalists, mostly Sunnis, from the upcoming election.
That purge was ordered by a committee led by two prominent Shia legislators who are believed to have ties to Iran and also are running in the election.