LONDON—World stocks held at a one-year low on Tuesday, while gold climbed above the key $2,000 level, as the prospect of a ban on Russian oil imports pushed up oil prices and raised concerns of soaring inflation and slowing economic growth. Russia warned that oil prices could surge to $300 a barrel and it might close the main gas pipeline to Germany if the West halts oil imports over the invasion of Ukraine. International oil benchmark Brent crude, which briefly hit more than $139 a barrel in the previous session, was up about 2.6 percent at $126.42. Still, with Europe rejecting plans to ban energy imports, there was some relief and European stocks picked up more than 1 percent in early trading, although some analysts said that may be a temporary reprieve. Since mid-February, European banks have lost a quarter of their share value and an earnings hit looks inevitable. …