By Charlie Conchie Aviva and Lloyds are among a group of City firms to throw their weight behind the government’s National Wealth Fund today in a boost to Rachel Reeves’s plans to push private sector investment into the economy. The Investment Delivery Forum, founded by seven of the UK’s biggest insurance and long-term saving firms, has pledged to pump billions of pounds into Reeves’ new wealth fund and finance the development of areas like electric vehicles and nuclear energy infrastructure. “Members of the Forum stand ready to act to accelerate the nation’s investment into green and good inf…