Russia has accused Nato and the US of “provoking a new level of tension” after the US and Germany became the latest allies to let Ukraine’s military to use Western-supplied weapons to strike targets inside Russia.A Berlin spokesman said Germany was convinced Ukraine had the right to defend itself from Russia, especially from cross-border attacks on its second largest city Kharkiv.US officials said American-supplied weapons could be used to counter Russian fire near the Kharkiv region, either where Russian forces were “hitting them or preparing to hit them”.Ukraine’s President Volodymyr…