LONDON—The euro briefly sank below parity versus the Swiss franc for the first time in seven years on Monday and held at a 22-month low versus the dollar as soaring oil prices stoked fears of a stagflationary shock that could hammer Europe. The conflict in Ukraine and harsh international sanctions on Moscow have sent Russian assets tumbling while prices of the country’s exports such as precious metals, oil, and gas have soared at a time when the global economy was already grappling with inflationary pressures. Europe is the most vulnerable as it imports as much as 40 percent of its natural gas consumption from Russia and the single currency has become increasingly correlated with oil prices—the higher oil climbs, the more the euro falls as investors fret about higher inflation and the blow to the economy. In early London trading on Monday, the euro was down as much as 0.5 …