Russian leaders have nothing to fear from a U.S. national missile defence and are ``off the mark'' in calling it a threat to arms control, Defence Secretary Donald H. Rumsfeld said Saturday. In his first interview since taking office two weeks ago, Rumsfeld told reporters traveling with him from Washington that the anti-missile system envisioned by the Bush administration will be too limited in scope to threaten the deterrent value of Russia's large arsenal of strategic nuclear weapons, AP reports. ``They know and we know and you know that the systems that are being discussed are not in any way relevant to the Russians''' nuclear force, which totals about 6,000 warheads and is shrinking, Rumsfeld said. Visit to Munich is the first trip abroad for Rumsfeld in his second stint as defence secretary. In the course of his trip private meetings with several of his NATO counterparts, including the defence ministers of Britain, Germany and Italy are scheduled. Asked whether the Bush administration intends to withdraw from the 1972 ABM treaty rather than negotiate with Russia to amend it, Rumsfeld said, ``That's an open question.'' “A treaty was written 25 years ago <…>when we were in a Cold War<…> That period is over in our life. Why don't we get over it?'' the Defence Secretary said.