UK's main stock index hit a three-week low on Wednesday amid a broad-based decline, after concerns over U.S. economic performance hit market sentiment ahead of a slew of central bank monetary policy decisions later this month.

The blue-chip FTSE 100 index was down 0.7%, as of 0715 GMT, after logging its steepest single-day decline in two weeks on Tuesday. The domestically-focused mid-cap FTSE 250 fell 0.9%, after its biggest drop in almost a month.

Medical equipment and household goods were the worst-hit sectors, down 2.1% and 1.4%, respectively.

Investor sentiment took a hit on Tuesday after an overall weak U.S. manufacturing data brought back jitters over the strength of the world's largest economy, which had sparked a global stocks rout in early August and deepened calls for a Federal Reserve interest rate cut this month.

While U.S. futures fell after the sharp Wall Street rout overnight, Europe's STOXX 600 also dropped 1% on the day.

While September has proved to be a weak month, if historical data is anything to go by, a bevy of factors could dictate the course of market performance. As a September U.S. rate cut is almost fully priced in, investors will be looking for clues to gauge the quantum of such a cut.

U.S. job openings data, euro-zone producer prices and UK's Purchasing Managers' Index will be in focus for the day, followed by rate decisions from the European Central Bank and the Bank of England in upcoming weeks.

Direct Line Insurance Group fell 2.3% after a half-year operating profit miss, while homebuilder Barratt slipped 1.2% after annual results.

Airtel Africa dropped nearly 6.4% to the bottom of the FTSE 100, after JP Morgan downgraded the stock to "Neutral" from "Overweight".

Insurer and asset manager M&G fell 1.2% after lower first-half operating profit.

(Reporting by Ankika Biswas in Bengaluru; Editing by Rashmi Aich)