The attacks on Saudi oil facilities sent a shudder through global markets on Monday (September 16). Big oil was the one big gainer. Shares in BP and Shell were up about 3% in early trade. They may be set for a windfall as crude prices soar. Oil futures rose close to a fifth at one point - their biggest one day gain since the 1991 Gulf War. For most other equities, that's yet another negative. Oil-dependent stocks like airlines are one obvious victim. Shares in Ryanair, EasyJet and Air France KLM were all among the losers. But the impact went much wider. With global growth already faltering, and U.S.-China tensions still high, analysts say an oil price shock is the last thing the world economy needs. Germany's Dax and France's CAC 40 indexes were both off more than half a percent from the open. Perceived safe havens like the Japanese yen and gold gained instead. UK markets looked a little different. Losses on the FTSE were more limited, as it's home to those soaring oil stocks. Optimism too that a Brexit deal might be possible. On Monday the government talked up the chances of reaching agreement at a mid-October EU summit.