Gold hit its highest in nearly three weeks on Monday, as turmoil in Iraq supported the metal's safe-haven appeal, while platinum group metals gained ahead of the outcome of wage talks to end a five-month long strike in South African mines.

Spot gold rose 0.1 percent to $1,278.21 an ounce by 0020 GMT, after hitting $1,278.74 earlier in the session – the highest since late May.

Sunni insurgents seized a mainly ethnic Turkmen city in northwestern Iraq on Sunday after heavy fighting, solidifying their grip on the north after a lightning offensive that threatens to dismember Iraq.

Gold is seen as a safe-haven asset at times of geopolitical uncertainties.

Hedge funds and money managers increased their bullish bets in gold futures and options in the week to June 10, their first increase in five weeks, according to data from the Commodity Futures Trading Commission on Friday.

Among other precious metals, platinum and palladium gained about 1 percent each on Monday after logging sharp declines last week on easing supply worries.

The leader of South Africa's AMCU union said on Friday a wage deal with the top three platinum producers was imminent, signalling a possible end to a crippling five-month strike that has disrupted global output of the metal. – Reuters