UPDATE 1-New Kingfisher boss faces worsening sales decline

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LONDON, Nov 20 (Reuters) - British home improvement retailer Kingfisher on Wednesday reported a worsening fall in underlying sales in its latest quarter, underlining the task facing its new boss.

In September, Carrefour veteran Thierry Garnier succeeded Véronique Laury as chief executive of the group, whose main businesses are B&Q and Screwfix in Britain and Castorama and Brico Depot in France. Its shares have fallen 15% over the last year.

Garnier said he would update on his strategy with full year results in March.

"My early assessment is that we have not found the right balance between getting the benefits of group scale and staying close to local markets," he said.

"We are suffering from organizational complexity, and we are trying to do too much at once with multiple large-scale initiatives running in parallel."

Kingfisher said its total sales fell 3.2% at constant currency to 3.0 billion pounds ($3.87 billion) in the three months to Oct. 31, its fiscal third quarter, while like-for-like sales fell 3.7%. That compares with a first half fall of 1.8%.

It said the drop reflected continuing disruption from new range implementations, lower promotional activity and ongoing operational challenges in France, and softer market conditions in its main markets.

Like-for-like sales dropped 6.1% in France and were down 1% in the UK and Ireland.

Kingfisher said initiatives to improve Castorama France's performance were underway with a key focus on IT effectiveness and supply chain efficiency.

It maintained its forecast for a flat gross margin for the full 2019-20 year. ($1 = 0.7745 pounds) (Reporting by James Davey; editing by Kate Holton)