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Aug 21 (Reuters) - Australia's Ampol Ltd (ALD) on Monday posted a 26% drop in its half-year profit, hurt by weak refining margins at its Lytton refinery in Brisbane and weaker pricing of its products, partly offset by higher sales volumes and contribution from Z Energy.

Ampol, which completed the acquisition of Z Energy in May last year, benefited from the full contribution of the New Zealand-based fuel distributor despite extreme weather events experienced in the first quarter.

Z Energy's earnings before interest and tax (EBIT) for the first half was A$122.8 million, helped by an uptick in sales volumes.

The country's biggest fuel supplier said net profit after tax from continuing operations came in at A$329.6 million ($210.88 million) on a replacement-cost basis for the six months ended June 30, compared with A$444.7 million a year earlier.

The Sydney-based firm declared an interim dividend of 95 Australian cents per share, down from last year's 120 Australian cents per share. ($1 = 1.5630 Australian dollars)