The central government has blocked plans to launch the doorstep delivery of rations from next week, sources in the Arvind Kejriwal administration said on Saturday, in the latest episode in the tussle between the two sides that share responsibilities in the capital. "The Delhi government had an ambitious plan to deliver rations to every household in Delhi at their doorstep. It would have helped 72 lakh people and was set to be implemented next week. But the central government said it can't go ahead since its clearance wasn't taken," sources said.