March 18 (Reuters) - Gold prices scaled a record peak above the key $3,000 mark on Tuesday for the second time within a week, as investors sought cover from economic concerns fuelled by U.S. President Donald Trump's tariff polices.

Spot gold prices hit a record high of $3,005.09 per ounce.

Historically considered a reliable store of value during times of geopolitical instability, gold has risen 14% so far this year. Since Trump took office in January, gold has hit a record high 14 times as trade tensions have led to growing safe-haven demand.

"With the price now reaching our long-held target of $3,000/oz, the main question is whether the rally will continue. We think so, as long as policy risks and an intensifying trade conflict continues to spur safe-haven demand," UBS said in a note. "We revise our target to $3,200/oz over all tenors (from $3,000)."

Trump has floated plans for a series of U.S. tariffs, from a flat 25% on steel and aluminium which came into effect in February, as well as reciprocal and sectoral tariffs that he said will be imposed on April 2.