"We have not forgotten and will never forget that the miracle of my country’s reunification and the end of Europe’s division would not have been possible without the courageous and human decisions that you personally made back then," the letter, published by Steinmeier’s office, read.
The German president regretted that not all hopes of those past days had been fulfilled and that Germany and Russia had drifted apart.
"What pains me the most is the state of the German-Russian and European-Russian relations. It is our mission and obligation not to accept the growing alienation of the past years or lose sight of our goal to build a common future based on peace and cooperation," the letter continued.
Steinmeier concluded by saying that Germany remained forever grateful to Gorbachev. He recalled their latest meeting in Moscow two years ago and wished the former Soviet leader good health, optimism and prosperity.
This month marks 30 years since the fall of the Berlin wall, which split the German capital into the Eastern and Western parts. Next year, Germans will celebrate the 30th anniversary of the nation's reunification.