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The failed bid to merge with rival Asda cost Sainsbury's £46m, the supermarket giant has said.

In April, a proposed merger between Sainsbury's and Asda was blocked by the UK's competition watchdog over fears it would raise prices for consumers.

Sainsbury's said that like-for-like sales growth continued to slow in the fourth quarter, especially over the Christmas period.

It added it would accelerate investment in its store estate and technology.

Fourth-quarter sales fell 0.9%, having fallen 1.1% over Christmas.