Germany has begun work on a large-scale investment programme designed to revive growth and shore up investor confidence in Europe’s biggest economy, according to a report in business daily Handelsblatt. People familiar with the plan said the initiative is being shaped jointly by leading German companies, including Siemens AG and Deutsche Bank AG, and aims to channel fresh capital into domestic projects that can accelerate productivity and sustainable expansion. Details on the size of the package and its financing have not yet been disclosed, but backers told Handelsblatt the effort will be marketed as a “historic investment offensive” to signal confidence to international investors unnerved by weak output data and geopolitical tensions.