The Union State of Belarus and Russia. What if it happened? Alexander Lukashenko of Belarus and Vladimir Putin of Russia sign the Constitution of the Union State, proposing Belarus as the core and key state of the newly formed Union State, and designating Minsk as the capital of the Commonwealth. With this, international response especially from Ukraine and the United States emerged. Some say it was the start of a new Soviet Union, some say it was a major step for two of the strikingly similar countries to become one once again.