The US could take a lead role in monitoring a buffer zone between Ukraine and Russia if and when a peace deal is reached, US broadcaster NBC News reported on Friday. The buffer, envisaged to protect Ukraine from further Russian attacks, would be a large demilitarised zone and could additionally be secured by troops from one or more non-NATO countries such as Saudi Arabia or Bangladesh, the report said, citing four people familiar with the matter. Separately, however, NBC News reported that President Donald Trump has grown increasingly pessimistic about the prospect of being able to broker an end to the conflict anytime soon, or seeing the Russian and Ukrainian presidents meet in person. Trump hosted Russian President Vladimir Putin...