The results were posted by parent Hong Kong Exchanges and Clearing Ltd (HKEx) (>> Hong Kong Exchanges and Clearing Limited), which has been seeking to boost returns from the world's biggest industrial metals market after a costly takeover.

At the 138-year-old LME, earnings before interest, tax, deprecation and amortisation (EBITDA) doubled to HK$322 million (£26.5 million) in the first three months of the year, HKEx said in a statement.

The jump in profit was largely due to a 31-percent hike in LME transaction fees that took effect at the start of the year, HKEx added.

Before the $2.2 billion (£1.4 billion) takeover by HKEx in December 2012, the LME was owned by the banks and brokers that used it and therefore trading fees were kept very low for members.

Some LME members objected to the fee increase, saying it would be likely to force brokers and banks to ditch some commission-free terms and review their business models.

The HKEx results statement showed the average daily volume of metals contracts traded on the LME fell 1 percent to 695,771 lots, although total futures market open interest was 6 percent higher at the end of the quarter.

It did not offer an explanation for the weaker volumes.

Profit was also helped by a 19 percent fall in expenses, mainly due to the reversal of HK$7 million of legal fees, HKEx added.

In March, HKEx said the LME was paid HK$15 million by Russia's Rusal (>> United Company Rusal Plc) after the aluminium producer lost a lawsuit over warehouse reform.

Overall HKEx first quarter profits gained by a third due to bumper trading volumes in a sign the exchange is moving to a 'new normal' level of activity that could cement its place among the world's top stock markets.

(Reporting by Eric Onstad, editing by Louise Heavens)