The United States is accelerating its delivery of Abrams tanks to Ukraine in an effort to bolster the country's defenses against Russian-backed separatists. The Pentagon has decided to send a refurbished older model of the tank, which can be ready in eight to ten months, instead of the newer M1A2 Abrams, which could have taken a year or two to build and ship. The Abrams tanks, weighing 70 tons, are considered to be some of the most powerful battle powerhouses in the world. The United States has already supplied Ukraine with Javelin anti-tank missiles, as well as other military equipment, as part of an effort to strengthen the country's defenses. The United States has been a vocal supporter of Ukraine's fight against Russian-backed separatists, who have been waging a conflict in the country since 2014. The conflict has killed over 13,000 people, and the United States has sought to increase its military assistance to Ukraine in order to help the country defend itself against further aggression. The accelerated delivery of the Abrams tanks is seen as a major step in this effort, and is likely to further escalate tensions between the United States and Russia. In response, the Russian government has warned the United States against providing Ukraine with additional military aid.