Aug 12 (Reuters) - Australian shares were set to open lower on Monday due to investors' concerns about an escalation of the prolonged Sino-U.S. trade spat. U.S. President Donald Trump on Friday said that while talks with China were continuing, he was not ready to make a deal and called a September round of trade talks into question. The local share price index futures fell 0.3% to 6,499, a 85.4-point discount to the underlying S&P/ASX 200 index close. The benchmark ended 0.3% higher on Friday. New Zealand's benchmark S&P/NZX 50 index rose 0.1% to 10,884.92 in early trade. (Reporting by Shriya Ramakrishnan in Bengaluru Editing by Bill Rigby)