(Adds previous year figures) Feb 6 (Reuters) - Australian...

(Adds previous year figures)

Feb 6 (Reuters) - Australian supermarket chain Coles Group (COL) on Thursday warned of a drop in operating earnings in the first half of fiscal 2020, citing margin pressure at its liquor business.

In a surprise update, the company pointed to higher costs from promotional and clearance activities, just 12 days ahead of its half-yearly results, scheduled for Feb. 18.

Coles forecast earnings before interest and tax of A$710 million to A$730 million ($478.82-$492.31 million) for the first half, lower than A$733 million a year earlier.

Meanwhile, a better Christmas period drove growth in comparable sales in its supermarket business to 3.6% in the second quarter, up from 0.1% growth in the first.

Coles said it expects comparable sales growth of 2% in the first half, compared with 3% a year earlier.

The company said operating earnings at its supermarket business also benefited from the removal of plastics bags and lower spending on promotions. ($1 = 1.4828 Australian dollars)