Simplify the following text for a Grade 17 native English-speaking person.
Original: While the Agreement was repudiated and condemned by Unionists , it was said to become the basis for developing trust and common action between the governments , which in time would ultimately bring about the Downing Street Declaration of 1993 , and the subsequent republican and loyalist cease-fires .
Simplified: While the Agreement was repudiated and condemned by Unionists , it was said to become the basis for developing trust and common action between the governments , which in time would ultimately bring about the Downing Street Declaration of 1993 , and the later republican and loyalist cease-fires .