Complex sentence: In August 1991, Latvia and Estonia immediately declared the restoration of their full independence (following Lithuania's 1990 example), while the other twelve republics continued discussing new, increasingly looser, models of the Union.
Split into simpler sentences: In August 1991, Latvia and Estonia immediately declared the restoration of their full independence (following Lithuania's 1990 example). The remaining twelve republics initially continued discussing new, increasingly looser, models of the Union.