The US has rejected Russia's demand to bar Ukraine from Nato, amid warnings Russia might invade its neighbour. Secretary of State Antony Blinken was giving Russia a formal response to its demands to resolve the Ukraine crisis.<br />'' <br />'' Mr Blinken said that he was offering Russia "a serious diplomatic path forward and it should accept this.<br />'' <br />'' In reply, a Russian minister said his country would study Mr Blinken's response, delivered in coordination with Nato.<br />'' Russia had issued a written list of its concerns about the expansion of the  NATO military alliance and related security issues.<br />'' <br />'' Among them was a demand for  NATO  to rule out the possibility of Ukraine and others ever joining the alliance.<br />''