There are several antonyms for the phrase "forcing up on", which means to impose something on someone forcefully. The first antonym is "encourage", which means to inspire or motivate someone to do something willingly. Another antonym is "persuade", which means to convince someone through reasoning or argument. "Negotiate" is another antonym, which means to discuss and come to an agreement that is acceptable to both parties. "Cooperate" is also an antonym, which means to work with someone and mutually achieve a goal without force. Overall, there are various alternatives to "forcing up on" that involve mutual understanding and agreement between parties.