By Tom Balmforth KYIV (Reuters) -The new commander of Russian forces in Ukraine made a rare acknowledgment of the pressures they are under from Ukrainian offensives to retake southern and eastern areas that Moscow claims to have annexed just weeks ago. And in another sign of Russian concern about the situation on the ground eight months into its invasion, the Kremlin-installed chief of the strategic southern region of Kherson on Tuesday announced an “organised, gradual displacement” of civilians from four towns on the Dnipro River. Russian forces in Kherson have been driven back by 20-30 km (1…