German chemicals group BASF and Russian investment vehicle LetterOne completed on 1 May the merger of their respective German-headquartered oil and gas businesses, Wintershall and Dea, in a deal worth €5.7bn ($6.4bn).

The firms say it will take approximately 12 months to complete full integration while parent companies BASF and LetterOne “expect to offer shares in Wintershall Dea through an Initial Public Offering (IPO) in the second half of 2020, subject to market...