The lender's stock rose as much as 9 percent and was last up 4.8 percent.
Bloomberg, citing people familiar with the matter, reported Germany plans on working on a merger between Deutsche Bank and Commerzbank. The report also said the government could look to change its tax law to help the merger go through.
Deutsche Bank has had a tumultuous 2018, with its shares falling more than 53 percent as it failed to revive revenue growth.
A spokesman at Deutsche Bank declined to comment. A spokesman at Commerzbank also declined to comment.
Click here to read the Bloomberg News report.