SOFIA — Bulgaria on Tuesday said it is planning reforms to its nationality laws, including scrapping the controversial "golden passport" scheme which offered citizenship to large-scale investors to the EU country.

"Part of the changes would be the abolition of obtaining Bulgarian citizenship through investment," the justice ministry said in a statement.

Since 2013 Bulgaria has made it possible to apply for citizenship in return for at least 500,000 euros (US$568,000) of investment.

The European Commission has expressed its concern that such schemes could pose a security risk and foster corruption.

In a report published in October, NGOs Transparency International and Global Witness said such schemes -- run by Austria, Bulgaria, Cyprus and Malta -- posed the risk of money laundering and were "an attractive prospect for the criminal and the corrupt".

A dozen other countries offer residency rights on the same basis and the report said that across the European Union 6,000 passports and 100,000 residency permits had been granted in the space of 10 years.

The justice ministry said Bulgaria’s scheme had "not actually achieved the goal of attracting foreign investment, creating jobs and contributing to growth".

The ministry also announced other changes designed to crack down on the abuse of the system whereby ethnic Bulgarians in other countries can claim citizenship.

Most of the roughly 15,000 naturalisations processed by Bulgarian authorities last year were of this kind.

In future applicants will have to "master the Bulgarian language and have a job and sufficient funds in Bulgaria", the ministry said.

Last October, several top officials were charged with taking bribes in exchange for certificates of Bulgarian ancestry that allowed bribe payers to obtain Bulgarian passports.

Also on Tuesday, Bulgarian authorities confirmed they had revoked the Bulgarian passport of Russian telecoms mogul Sergey Adoniev.

Adoniev was granted a Bulgarian passport in 2008 for "special merit" to Bulgaria -- an honour granted to foreigners with achievements in the public or economic domain or in the spheres of science, technology, culture or sport.

The justice ministry confirmed that his nationality had been revoked in May after a conviction in the United States for money laundering came to light. — AFP