(For a Reuters live blog on U.S., UK and European stock markets, click LIVE/ or type LIVE/ in a news window) * FTSE 100 down 1.7%, FTSE 250 off 1.3% Jan 29 (Reuters) - The FTSE 100 dropped on Friday and was set to record its worst week since October as stalled vaccine rollouts and lockdowns to curb the spread of contagious new coronavirus strains kept investors from jumping into riskier assets. The blue-chip FTSE 100 index dropped 1.7%, with energy and mining stocks being top drags for the week, while the mid-cap index fell 1.3%. The benchmark indices were also set to fall for the month, with the mid-cap index set to record its worst monthly loss since September. Drugmaker AstraZeneca fell 3.6% for the week and was one of the top drags on the blue-chip index as a tussle with the European Union on vaccine rollouts continued to weigh on the stock. The European Union’s contract with AstraZeneca for its COVID-19 vaccine contains binding orders, EU Commision Head Ursula von der Leyen said, demanding a plausible explanation from the drugmaker for delivery hold-ups. British online fashion retailer Boohoo fell 1.5% after it confirmed on Friday 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. (Reporting by Shashank Nayar in Bengaluru; Editing by Bernard Orr)