In May 1989 Matei helped found The Peoples' Front of Moldova as a member in the Council, in their Permanent Bureau, and as their spokesperson.

The study— The work of Nicolae Milescu Spătarul – a source for the study of the historical ethnology of the peoples of Siberia and of the Far East—was published in the year 1989.

[3] On 16 December 1990, he was the leader of the second Great National Assembly & wrote the proclamation for the independence of all Romanians from the territories occupied and annexed by the Soviets, and their right to reunite with Romania.

He also wrote The Proclamation (The Final Document) adopted by this meeting and participated at the Conference OSCE (The Organization for Security and Co-operation in Europe) in Copenhagen on behalf of the Republic of Moldova.

In 1993 and 1994 he was a member of the Permanent Bureau of the Intellectuals Congress, the director of the publishing house Hyperion, and editor of the weekly The Messenger.