Greece lost access to the financial markets in 2010 amid an unfolding sovereign debt crisis and, since then, it has struggled to revamp its economy — relying in the last eight years on creditors' money for financing. But this external help ended Monday, after three consecutive financial programs that imposed tough economic measures, from cuts in salaries and pensions to higher taxes.

"Greece has already undertaken quite a lot of commitments for the next two years that aren't dramatically different from another program," Panos Tsakloglou, an economics professor at Athens University, told CNBC's "Squawk Box Europe."

European and Greek politicians are in celebratory mode as Athens ended a decade of financial assistance on Monday . But, according to one expert, Greece remains in the hands of its creditors and is under an "informal" fourth bailout program.

Greece has little to cheer despite reaching an end to its third bailout program as austerity measures will remain with the country for at least two more years, one academic told CNBC Tuesday.

However, some of the measures that Greece had to legislate to end the third program only come into effect in the coming months and years, including changes to pensions, which kick in at the start of 2019.

"If you look at the yields of Greek bonds and especially the spreads (difference) from the German bund, they do not seem to guarantee a smooth reintroduction of Greece re-access to the international financial markets," Tsakloglou added.

Looking at the yield on the 10-year Greek government bond, it's still the highest across the euro zone, above 4.32 percent.

"Of course, these things (market conditions) can change in the next month, however as we are at the moment we are not in a celebratory mood here in Greece," he said.

Greek Prime Minister Alexis Tsipras is expected to address the media Tuesday in Ithaca island. Market players are looking for clues on what direction he will take the country now that Greece is no longer getting regular tranches of money from Europe. Instead it will have to use the global financial markets to help with its spending plans.

Athens is sitting on a cash buffer that will allow it sufficient funds for the next 22 months. This cash pile stands at 24.1 billion euros ($27.4 billion), thanks to money that Greece put aside during the third financial program and tranches from European creditors. The amount is expected to cover all sovereign needs in the coming year-and-a-half, unless it thinks there are favorable conditions to do so.

On Monday, European politicians called on Tsipras to continue a sound fiscal policy. However, analysts and investors worry that a general election in 2019 might affect the direction of economic policy in Athens.