US President Joe Biden has agreed “in principle” to hold a summit with Russian President Vladimir Putin to discuss the crisis over Ukraine. The talks proposed by France will only take place if Russia does not invade its neighbour, the White House said. The Kremlin, meanwhile, said there were no “concrete plans” for a summit. It is hoped that such talks could offer a possible diplomatic solution to one of the worst security crises in Europe in decades. US officials say intelligence suggests Russia is ready to launch a military operation, which Moscow denies.  The proposed summit was announced by the French presidency after two phone calls between President Emmanuel Macron and Mr Putin, which went on for almost three hours in total.(BBC)…[+]