(Adds other performance metrics, background on Coles spin-off)...

(Adds other performance metrics, background on Coles spin-off)

Oct 15 (Reuters) - Australian retail conglomerate Wesfarmers Ltd (WES) said on Monday that total first-quarter sales at its soon-to-be-spun-off supermarket division, Coles, grew 5 percent, helped by a promotional campaign and investments in its flybuys loyalty programme.

Sales came in at A$9.84 billion ($7 billion) for the three months to Sept. 30, the company said in a statement. It did not give prior guidance and analysts do not give quarterly forecasts for the company.

Comparable store sales jumped 5.1 percent over the period for Coles’ supermarkets division, compared with a 0.3 percent growth a year ago.

Meanwhile, comparable sales growth at the liquor division was 1.3 percent, a touch lower than last year.

Managing Director Rob Scott said in a statement that the results reflected "continued good momentum" at Coles.

It was Wesfarmers' last trading update about the Australian No. 2 grocery chain before it proceeds with a plan to spin it off next month and free up capital for higher-margin investments.

Coles has struggled for nearly a decade to take customers from larger supermarket rival Woolworths Group Ltd (WOW) as both companies stare down new cut-price competition from the likes of ALDI Inc and Costco Wholesale Corp COST.O .

($1 = 1.4065 Australian dollars)