Greek conservative New Democracy leader Antonis Samaras outlined his party's social and political reform agenda on Thursday, promising a tougher stance against crime and illegal migration and a leaner state if the conservatives win the May 6 general elections.

"Besides the agreements with international lenders to address the debt crisis, we need to sign a new social contract with Greek people to make reforms and meet goals," he told a party gathering in central Athens.

Expressing optimism that voters will grant the conservatives, who are frontrunners according to the latest opinion polls, a "strong mandate" to rule the debt-laden country, he presented the party's ideas to change the model of governance and boost security and social coherence.

Samaras called for a constitutional review to introduce the election of the Greek president by the people instead of the parliament, as well as the reduction of the number of deputies from the current 300 members and the number of ministries to 10.

In an interview with a local website, Evangelos Venizelos, the leader of the socialist PASOK party, expressed similar views. Both parties back the bailout deals with international lenders that have averted a chaotic default for the country.

According to Greek political analysts, since no party may secure a clear parliamentary majority, a new ND-PASOK coalition could emerge from the ballot.

In regard to education and health reforms, the conservative party chief suggested setting up private universities and the merging of state-run hospitals to save costs.

Samaras pledged a strict line against illegal migration, crime and hooded anarchists, who have regularly mingled with peaceful protestors during anti-austerity rallies over the past two years, clashed with police and caused chaos.

Samaras said his party will seek bilateral agreements for the repatriation of illegal immigrants.

According to official figures from the Citizen's Protection Ministry, some 130,000 people immigrated illegally to Greece on an annual basis over the past decade. The issue has dominated the pre-election campaigning along with economic policy.