LONDON: The export-laden FTSE 100 index closed lower on Tuesday, weighed down by miners and a stronger pound, while an unexpected drop in retail sales kept risk sentiment at bay.

The blue-chip London index fell 1.1% and the mid-cap FTSE 250 dropped 0.6%, abandoning gains made on optimism from a pledge by Washington and Beijing to stand by their Phase-1 trade pact.

Oil & gas companies and miners were among the top decliners by the closing bell.

British retailers have cut the most jobs since the depths of the financial crisis and expect the pace of losses to accelerate, the Confederation of British Industry said.

Sterling gained despite the monthly retail sales balance unexpectedly falling to -6 in August from July's 15-month high of +4.

The FTSE 100 is still on course for its best month since April 2018 even as concerns linger about a choppy economic recovery after a record contraction in the second quarter.

AstraZeneca Plc rose 0.1% after launching a trial for an antibody-based treatment for Covid-19.

Aveva Group rose 7.3% as it said it would buy OSIsoft, a privately held maker of industrial software used to manage plants and factories, for an enterprise value of $5 billion.

Retailer DFS Furniture Plc jumped 10.7% after saying its performance over the last six weeks was significantly above its initial expectations.