Spot gold was down 0.3 percent at $1,220.27 an ounce at 0703 GMT.
U.S. gold futures for August delivery were 0.4 percent lower at $1,220.20 an ounce.
• The dollar index, which measures the greenback against a basket of six major currencies, was up 0.2 percent at 94.838. It hit a one-year high of 95.652 last week.
• "In addition to the U.S. dollar, there has been little follow through on the Trump and Rouhani war of words and frankly the overall reaction on risk sentiment was muted," said Stephen Innes, APAC trading head, OANDA.
"I think the market realises the chance of this escalation leading to a U.S. military reprisal is overblown."
• Iran on Monday dismissed an angry warning from U.S. President Donald Trump that Tehran risked dire consequences if it made threats against the United States.
• Trump on Sunday warned Iranian President Hassan Rouhani not to threaten the United States again, after Rouhani cautioned Trump about pursuing hostile policies against Tehran.
• Meanwhile, benchmark 10-year U.S. Treasury yields rose to their highest in five weeks on Monday as the Federal Reserve was seen as likely to continue raising interest rates despite criticism from U.S. President Donald Trump.
• Spot gold looks neutral in a range of $1,214-$1,237 per ounce, Reuters technical analyst Wang Tao said.
• Holdings of SPDR Gold Trust, the world's largest gold-backed exchange-traded fund, rose 0.55 percent to 802.55 tonnes on Monday, its highest in over two weeks.
• In other precious metals, silver was nearly unchanged at $15.37 per ounce.
• Gold attempted to break out above last Friday’s high but the breakout was met with bearish pressure and the metal traded down for the most part of the day.
Gold broke below the 200-period simple moving average and 1,225.90 support but price pulled back up and bulls are currently trying to create a reversal above the1,220.90 level.
Sustained prices above 1,225.90 can lead to a retest of 1,232.00 while a failure below the level can lead to the resumption of the main bear trend towards 1,211.17, the current 2018 low.