Greece's coveted golden visas, increased to €500,000, are finally coming into effect.

The cost of a Greek "golden visa" in the most popular areas of the country has doubled and is now €500,000.

The Greek government has amended its investment visa program, which grants five-year residency rights to foreign nationals who have invested at least €500,000 in capital investment, business or real estate.

The announcement of an increase in the cost of the Golden Visa in Greece last year, as well as Portugal's recent decision to impose restrictions on its popular Golden Visa program, has caused a surge of interest.

Thousands of Americans and Chinese investors bought real estate in Greece before the increase in value, which was one of the reasons for delaying the introduction of the measure.

Greece introduced its "golden visa" program in 2014, granting a five-year residence permit to foreign nationals who purchase property worth at least €250,000.

Figures from the Ministry of Immigration and Asylum, as reported by Greek City Times, show that in the first five months of this year, the golden visa program generated almost €1 billion for the Greek economy.

Increased buying interest ahead of the introduction of the new measures caused more than 5,500 'visa-by-investment' applications to be delayed. The total value of properties sold during the period amounted to €975 million, triple the previous year's figures.

Greece's decision did not please the European Union, which is calling for the abolition of all "golden visa" programs. The Commission believes that selling citizenship and residency to wealthy foreigners without a residency requirement contravenes EU norms and poses a security risk.

Changes to Greece's golden visa program will come into effect in the northern part of the country, central and southern Athens in the Attica region, the islands of Mykonos and Santorini and the municipality of Thessaloniki. In the remaining areas, the minimum value will remain €250,000.