Denmark plans to invest an additional 13 billion kroner ($2 billion) in its tax agency after a series of scandals, Tax Minister Karsten Lauritzen said.

The amount matches what the government has invested over the last four years and will bring the agency’s workforce to 10,000 by 2025, according to a presentation by the minister in Copenhagen.

Previous governments under Lauritzen’s Liberal Party had cut costs and staff at the agency, leaving it vulnerable when offshore clients claimed about 12.7...