Sentence 1: russia ratified the updated treaty in 2004 but the united states and other nato members have refused to do so arguing that moscow must first fulfill obligations to withdraw forces from georgia and from moldova's separatist region of trans-dniester. 
Sentence 2: russia has ratified the amended version but the united states and other nato members have refused to do so until the russian government withdraws troops from the former soviet republics of moldova and georgia.
Similarity: 0.8400000000000001