SINGAPORE: The US has offered North Korea "unique" security guarantees to try to persuade it to give up its nuclear arsenal, Secretary of State Mike Pompeo said on Monday ahead of Tuesday’s crucial summit in Singapore.The talks were advancing faster than expected but were still ongoing with little more than 12 hours to go before Kim Jong Un sits down with Donald Trump, Pompeo told reporters.The meeting, long sought by Pyongyang, will be the first ever between a serving US president and a...