Ukrainian soldiers are laying seige to Donetsk, where pro-Russian rebels have taken control.<br/> <br />After heavy fighting, much of the town remains in ruins.<br/> <br />But the soldiers are also preparing for a larger battle. They believe Russia is preparing to invade.<br/> <br />NATO is warning that Russia could use the pretext of a humanitarian mission to send in the 20,000 combat-ready troops now positioned on Ukraine's border.<br/> <br />Ukrainian Defence Council spokesman Andriy Lysenko says the military will be ready to respond:<br/> <br />(SOUNDBITE) (Ukrainian) UKRAINIAN NATIONAL SECURITY AND DEFENCE COUNCIL SPOKESPERSON, ANDRIY LYSENKO, SAYING:<br/> <br />"If there is direct aggression, then it is obvious that there will be an adequate answer from all branches of Ukrainian armed forces."<br/> <br />The battle between Ukraine government troops and separatist rebels has been raging since April.<br/> <br />Economic sanctions from the west, and threats of further action against Russia, have had little affect.<br/> <br />.
