The German government expects economic growth of 0.5 percent this year, business daily Handelsblatt said on Tuesday, citing a report due to be published after cabinet discussions on Wednesday, down from an earlier estimate of 1.0 percent.
But a government source told Reuters the 2013 forecast had not been set and would be published after cabinet discussions on Wednesday.
The paper said growth in Europe's largest economy should accelerate after a slow start to reach 1.25 percent year-on-year in the final quarter of this year.
Economists polled by Reuters expect the German economy to have grown by 0.8 percent in 2012 after it expanded by a robust 3 percent in 2011. The paper said growth last year would be 0.75 percent.
The level of unemployment is not expected to change much in 2013, Handelsblatt said, with the number of jobless seen rising by just 60,000 over the previous year to 2.95 million.
Unemployment stood at 6.9 percent in December, with 2.942 million people out of work.
The main threat to Germany's economic prospects remained the euro zone debt crisis, the paper said.