'Heavy Fighting' in Ukraine, Reports Britain’s Defense MinistryBritain’s Defense Ministry said early Saturday that in the last 48 hours heavy fighting has been taking place as Ukrainian forces have continued their offensive against Russian forces in Kherson Oblast, west of the River Dnipro. In the statement posted to Twitter the ministry said “Russia is likely attempting to slow the Ukrainian attack using artillery fire along the natural barrier of the Ingulets River, a tributary of the Dnipro. Simultaneously, the supply lines of the Russian force west of the Dnipro are increasingly at risk." In another development, the credit rating firms of Fitch and Scope have downgraded Ukraine to just one step above default. The move followed Ukraine’s request for a debt payment freeze. The rating agencies said that makes a default on the debt more likely. Meanwhile, the U.S. has promised Ukraine a new $270 million security assistance package, which will include four more High Mobility Artillery Rocket Systems, or HIMARS. Ukraine's military has already deployed at least eight HIMARS to the front lines in its fight against Russia, while another four are either on the ground or on their way. The latest U.S. pledge will bring the total number of HIMARS to 16. In addition, Ukraine has deployed six medium- to long-range rocket systems from Germany and Britain. Ukraine and Russia signed separate deals Friday, opening the way for Ukraine to export millions of tons of grain worldwide. Ukraine, one of the world’s major breadbaskets, has been unable to export its grain because of the Russian invasion. “About 20 million tons of last year's grain harvest will be exported. And also it will be possible to sell this year's harvest, ... already being harvested,” Ukrainian President Volodymyr Zelenskyy said during his daily address Friday. “These are the incomes of farmers, the entire agricultural sector and the state budget. These are jobs. These are funds for next year's sowing season.” Zelenskyy estimated that his country currently has approximately $10 billion worth of grain.