Bucharest - Romania’s government said Tuesday that diplomat Mihnea Constanescu, praised internationally for his efforts to combat anti-Semitism, has died. He was 57.

The foreign ministry said Constantinescu, who advised Romanian prime ministers from 1990-2012, died Sunday in Nice, France after a long illness.

US-based Jewish rights group Simon Wiesenthal Center called Constantinescu one of the “great figures of our generation in the fight against anti-Semitism.” Constantinescu chaired the International Holocaust Remembrance Alliance in 2016, contributing to the adoption of a working definition of anti-Semitism that year.

Calin Popescu Tariceanu, premier from 2004 to 2008, described Constantinescu as “Romania’s best ever public servant.” He said his natural modesty and discretion barred him from seeking high office.

Constantinescu helped Romania prepare for joining NATO in 2004 and the European Union three years later. In 2001, he played a key role when Romania chaired the Organization for Security and Cooperation in Europe.

His last job was as a government energy security adviser.

There was no word about survivors. Funeral plans were not made public.