(Reuters) - The FTSE 100 ended lower on Friday and recorded its worst weekly performance since October, as stalled vaccine rollouts and lockdowns to curb the spread of contagious new coronavirus variants kept investors from jumping into riskier assets. The blue-chip FTSE 100 index dropped 1.8%, with energy and mining sector being top drags for the week, while the mid-cap index fell 0.7%. Drugmaker AstraZeneca fell 3.7% for the week and was the third biggest drag to the FTSE 100 on Friday as a tussle with the European Union on vaccine rollouts weighed on the stock. However, Europe’s medicines regulator recommended approving the drugmaker’s COVID-19 vaccine for people over the age of 18, the third vaccine to be cleared for use in the European Union. “Clearly, there have been a few new concerns with the relationship with the European Union on the vaccine in recent days and that hurt the markets. It has also led people to take some profits,” said Chris Bailey, a strategist at Raymond James. The benchmark indexes were set to post a fall for the month, with the mid-cap index on track to record its worst monthly loss since September. Both indexes reversed their 2021 gains to trade lower by nearly 1% for the year. The internationally focused FTSE 100 has recorded consistent monthly gains since November, but recently lost steam and currently trades at a near six-week low, led by worries of elongated economic pain due to a surge in virus cases and lockdowns. Life insurer Prudential was the top loser this week, falling nearly 16% on equity raise and demerger plans, while major brokerages including Deutsche Bank, UBS and Bank of America trimmed their target price on the stock. Online fashion retailer Boohoo gained 1.5% after it confirmed it was in exclusive talks with the administrators of Philip Green’s collapsed Arcadia group over the purchase of the Dorothy Perkins, Wallis and Burton brands.