LONDON—European stocks edged lower on Thursday and were set for their biggest quarterly drop since the start of 2020, while oil prices fell and eastern Ukraine braced for fresh attacks. The MSCI World Equity index was down 0.3 percent on the day, while Europe’s STOXX 600 eased 0.2 percent to sit just below a one-month high hit on Tuesday. European indexes strengthened earlier in the week as investor sentiment became more positive about Ukraine peace talks. But optimism petered out after Ukrainian President Volodymyr Zelenskyy said that no quick resolution is expected and the country prepared for new Russian attacks. The STOXX 600 was on track for a 5.8 percent drop in the first quarter of 2022, its biggest quarterly fall since it plunged 23 percent in the first three months of 2020. U.S. stock futures pointed to a slightly more upbeat Wall Street session, but the S&P 500 was …