Volkswagen said it will launch almost 70 new electric models by 2028, accelerating its rollout of zero-emission cars.

This comes as its latest earnings revealed the operating margin at its core brand had taken a hit from new emissions tests. 

The profit margin at its core VW brand slipped to 3.8% last year, down from 4.2%, as higher investments into electric cars and challenges getting combustion-engined vehicles certified ate into profits. 

Volkswagen released full earnings today after pre-releasing earnings in February, when it said its 2018 group operating profit came in at €13.92 billion.

This was 0.7% higher than the previous year and below €14.53 billion forecast in a poll. 

The carmaker's Audi and Porsche brands made up the lion's share of VW Group's operating profit. 

Before special items, Audi's operating profit accounted for €4.7 billion and Porsche's €4.1 billion. 

Its VW brand delivered €3.2 billion in operating profit before special items, the carmaker said. 

As a result of the electric cars model ramp up, Volkswagen expects to build 22 million cars on its electric vehicles platforms PPE and MEB by 2028, up from the carmaker's previous estimate of 15 million cars.

Volkswagen stuck to its outlook, reiterating that it expects revenues to grow up to 5%, and to deliver an operating return on sales at group level of between 6.5-7.5% in 2019.