German media giant Bertelsmann said Thursday that its traditional book publishing business was the main driver of growth in the first three months of the current year.

"The year started well for Bertelsmann," said chief executive Thomas Rabe.

"We achieved a record operating result, to which our strategic actions in particular contributed, such as the combination of Penguin and Random House," Rabe said.

The group also made "significant progress" in expanding its education business in the first quarter, he added.

In the period from January to March, net profit jumped 35 percent to 143 million euros ($162 million). Underlying or operating profit rose by 6.7 percent at 463 million euros and revenues expanded by 0.5 percent to 3.92 billion euros.