Barclays plans to invest £1bn in green bonds in a move that will treble its involvement in financing environmentally-friendly schemes.Barclays said it will buy the bonds by November next year from issuers such as the European Investment Bank, World Bank, International Finance Corporation and the European Bank for Reconstruction and Development.Green bonds are fixed income securities aimed at raising cash to fund low-carbon schemes such as projects to reduce greenhouse gas emissions. Barclays currently has green bond investments worth £430m.Barclays said it would keep looking at investing in new supra-national organisations and government-issued bonds as they became available."Barclays will review its commitment to the green bonds sector on an ongoing basis, with the potential to increase it depending on overall growth of the sector," it said.Shares in Barclays had fallen 0.5p to 233.65p by 13:40 in London.