Question: When did the ussr agree to a unified germany inside of nato?

Disambiguated questions and answers:
context: Horst Teltschik, Kohl's foreign policy advisor, later recalled that Germany would have paid "100 billion deutschmarks" if the Soviets demanded it. The USSR did not make such great demands, however, with Gorbachev stating in February 1990 that "The Germans must decide for themselves what path they choose to follow". In May 1990 he repeated his remark in the context of NATO membership while meeting Bush, amazing both the Americans and Germans. This removed the last significant roadblock to Germany being free to choose its international alignments, though Kohl made no secret that he intended for the reunified Germany to inherit West Germany's seats in NATO and the EC.
question: When did Gorbachev express agreement with a unified Germany inside of NATO?
short_answers: May 1990
wikipage: German reunification
context: No context provided
question: When did the USSR formally agree to a unified Germany inside of NATO?
short_answers: 12 September 1990

Long-form answers:
knowledge: content: German reunification (German: Deutsche Wiedervereinigung) was the process in 1990 in which the German Democratic Republic (GDR) became part of the Federal Republic of Germany (FRG) to form the reunited nation of Germany.
wikipage: German reunification
content: he USSR did not make such great demands, however, with Gorbachev stating in February 1990 that "The Germans must decide for themselves what path they choose to follow". In May 1990 he repeated his remark in the context of NATO membership while meeting Bush, amazing both the Americans and Germans.[31]​ This removed the last significant roadblock to Germany being free to choose its international alignments, though Kohl made no secret that he intended for the reunified Germany to inherit West Germany's seats in NATO and the EC.
wikipage: German reunification
content: The Treaty on the Final Settlement with Respect to Germany (German: Vertrag über die abschließende Regelung in Bezug auf Deutschland[a]), or the Two Plus Four Agreement (German: Zwei-plus-Vier-Vertrag;[b] short: German Treaty), was negotiated in 1990 between the Federal Republic of Germany and the German Democratic Republic (the eponymous Two), and the Four Powers which occupied Germany at the end of World War II in Europe: France, the Soviet Union, the United Kingdom, and the United States. In the treaty, the Four Powers renounced all rights they held in Germany, allowing a reunited Germany to become fully sovereign the following year.
wikipage: Treaty on the Final Settlement with Respect to Germany
long_answer: German reunification was the process in 1990 in which the German Democratic Republic became part of the Federal Republic of Germany to form the reunited nation of Germany. In May 1990, Gorbachev expressed agreement with a unified Germany inside of NATO and removed the last significant roadblock to Germany being free to choose its international alignments. The USSR formally agreed to a unified Germany inside of NATO on 12 September 1990, when they signed the Treaty of the Final Settlement with Respect to Germany. The Treaty on the Final Settlement with Respect to Germany, or the Two Plus Four Agreement, was negotiated between the Federal Republic of Germany and the German Democratic Republic, and the Four Powers which occupied Germany at the end of World War II in Europe: France, the Soviet Union, the United Kingdom, and the United States and it renounced all rights the Four Powers held in Germany, allowing a reunited Germany to become fully sovereign the following year.