A new round of Greece's bailout program review resumed Wednesday with hope the two sides bridge the gap on the next set of fiscal adjustment and reform measures.

As Greek Finance Minister Euclid Tsakalotos re-launched dialogue with the heads of Greece's international creditors' representatives in the Greek capital, protesters once again took to the streets to reject austerity and reforms.

Foreign envoys left Athens in February with empty hands, as negotiations hit an impasse in particular on the pension system reform which triggered massive protests by several professional groups in Greece throughout the winter.

Ahead of Wednesday's meeting, Greek ministers repeated that the left-led government would not accept further cuts on primary pensions, arguing that many pensioners in recession-hit Greece also support their children and grandchildren.

On the agenda of discussions will be reform of the taxation system, the establishment of a new privatization fund, the fiscal gap until 2018 and non-performing loans.

Athens is pushing for the completion of the review of Greece's economic reform commitments -- initially scheduled to finish in late 2015 -- by May so that the discussion on debt relief starts as soon as possible.

However, there seems to be a great distance separating the two sides in several key topics, financial analysts and media commentators said.

Beyond lenders' requests for more reform, the government faces increasing pressure by labor unions that continue anti-austerity and anti-reform mobilizations, warning of more strikes.

On Wednesday, the umbrella unions of private sector workers GSEE, the union representing public servants ADEDY and the Hellenic Confederation of Professionals, Craftsmen & Merchants (GSEVEE) held a symbolic march to the Greek parliament.

Demonstrators denounced the government's arguments that the reforms will help create a sustainable pension system, a fair taxation system and lead Greece out of its debt crisis.

Protesters argued new policies under discussion would add an unbearable burdens on the average Greek household and enterprise, leading to more layoffs, foreclosures of homes and the collapse of the social security system.

Trade unions have announced that they intend to call a 48-hour general strike when the government submits the reform bill to the Greek parliament.

A dozen people briefly held a sit-in protest at the entrance of the EU Commission building in central Athens protesting austerity, as well as the handling of the refugee crisis.