German Chancellor Angela Merkel sent a message of confidence in Greek economy during a visit to Athens Friday, praising her hosts for the progress achieved in the battle to exit the financial crisis, a day after the country successfully returned to international bond markets for borrowing for first time since 2010.

In her second visit to Athens since the beginning of the crisis, the German leader pointed to Greece's growing potential after the painful austerity and reform program, warning that the country must continue on this difficult road of changes to reach full economic recovery through development.

"After the necessary structural reforms which will be necessary in the future as well, Greece has more possibilities rather than difficulties, despite high unemployment rates and the fact that growth and progress are not yet felt by many people," she said after talks with Greek Prime Minister Antonis Samaras and a meeting with young entrepreneurs.

"There are strong signals showing that the great efforts beared fruits, that major steps forward have been taken. I am aware of the difficulties working people, the unemployed and youth have been through and there will be more difficulties ahead, because the course is not over. However a lot has been achieved," she stressed.

The main goal from now on after the positive results of fiscal consolidation which however fuelled recession is to boost growth by supporting businesses, she said, pledging Germany's further support.

In regards to Athens' request for a discussion over a further debt relief for Greece following the progress made, Merkel pledged that it could start next autumn on better terms.

The German leader sealed her visit launching a Greek investment fund for growth which is established with Germany's financial support along the lines of the German state-owned development bank KfW.

The new Institute for Growth is expected to focus on the financing of small and medium-sized businesses with low interest rate loans.

"With the sacrifices of Greek peoples and the solidarity of our counterparts and German people our country today faces a different fate. Greece made it. Today is a new day," the Greek Premier said on his part, stressing that Greece will stick to reforms to further strengthen its competitiveness and will not be in the need of further bailout aid.

"Our vision regards a country who in its next steps towards growth will show what is needed; extroversion, innovation and emphasis on the commerciability of its products and services," he added.

Over the past four years, Greece has been kept afloat with multi- billion-euro bailout funding by European Union and International Monetary Fund in exchange of harsh cuts on wages, pensions, tax hikes and reforms which have fuelled jobless and poverty rates, recession and public disgruntlement.

Despite the escape from the threat of default and the impressive improvement on fiscal figures, the average Greek is still suffering, blaming partly Merkel for her government's pro-austerity stance in the management of the crisis across Europe.

As the German leader exchanged views with Samaras, hundreds joined a symbolic anti-austerity rally organized by trade unions and Left opposition parties in central Athens, defying a ban on protests by police.

Authorities had taken draconian security measures, in particular after a strong bomb blast hit the headquarters of the central Bank of Greece in the heart of the Greek capital on Thursday morning, causing damage but no injuries.