"The government is committed to holding parliamentary elections on time on the basis of the existing law from 2000," he told reporters after meeting Maronite Christian Patriarch Nasrallah Butros Sfeir.
"We will now make efforts to see if it is possible to look into the 2000 law, perhaps amending some constituencies."
Lebanon's disparate opposition to Syria's grip is unravelling along sectarian lines as the 29 May first round of the polls approaches.
It will be the first ballot without a direct Syrian presence in Lebanon in 33 years, and most Christians strongly object to the law organising it.
Christian leaders, from top officials loyal to Syria to vehemently anti-Damascus bishops, have slammed the electoral law, designed in 2000 to help Damascus allies win seats in the chamber they now dominate.
But with Syria ending its 29-year military and intelligence presence last month, Christian loyalists have turned against the law, which carves the country into a mixture of smaller and larger electoral districts.
The Taif Accord, which ended the 1975-1990 civil war that split Lebanon into Christian and Muslim enclaves, divides parliament's 128 seats in half between Muslims and Christians, whatever the rules.
But the influential Maronite bishops warn the 2000 law would upset the country's delicate sectarian balance by drowning out Christian voices in large voting districts dominated by Muslims.
Syrian was pressured to
withdraw from Lebanon
"We want Muslims and Christians to vote together but in small constituencies so they ... can act freely and choose the people with whom they have ties and who they know will represent them," Sfeir said on Friday.
"We hope the officials will try to respond to these legitimate popular demands."
Time running out
With the first round of elections nearing, time is running out to amend or replace the 2000 law.
Opposition figures had led calls for the election to take place on schedule by the end of May. Yet many Christian politicians, who objected to the 2000 law from the outset but lacked the parliamentary weight to reject it, are now rallying around Sfeir.
President Emile Lahoud opposes
the electoral law
Some Christian deputies are saying they would rather delay the polls so a new law can be devised and passed.
President Emile Lahoud, a Maronite loyal to Syria, has also opposed the law but is helpless in the face of parliament, led by pro-Syrian Shia Muslim Nabih Berri, who is well-served by the existing rules and refuses to call a vote on other formulations.
Opposition lawmakers on Thursday urged their leaders to meet and form joint slates to mitigate the drawbacks of the law.
It was not clear which leaders might meet, but the main figures include Sunni Muslim Saad al-Hariri, Druze leader Walid Jumblatt, Maronite former general Michel Aoun and Sitrida Geagea, wife of a jailed Maronite former warlord.
Al-Hariri, whose ticket is expected to sweep the Beirut poll on 29 May, was to declare the names this week. The announcement has been delayed because of opposition splits over who should fill the Maronite seat in Beirut. Candidates running in Beirut have until the end of Friday to register.
Sfeir says the 2000 law is unfair
to Lebanese Christians
Al-Hariri's father, former prime minister Rafik al-Hariri, was assassinated on 14 February in a car bomb attack in Beirut. His killing sparked large anti-Syrian protests and intense international pressure that forced Syria to withdraw in April.
But to the dismay of many Lebanese who had hoped the pullout would mark a fresh start, the opposition has unravelled over conflicting interests at the ballot box.