U.S. car giant General Motors has announced it will recall another 2.4 million vehicles in the U.S. because of safety concerns. That takes the total number of cars GM has recalled this year to over 13 million in the U.S. - more than the carmaker sold in 2013, according to BBC News.

The latest move covers possible faulty seat belts, transmissions, and air bags, as well as potential fire issues. No fatalities have been associated with this recall.

Most of the vehicles affected by the latest recalls were built between 2004 and 2010, although a small number of new cars and pickup trucks have also been included.

The company has been under intense pressure recently from regulators to improve its safety standards. Last week the company was fined $35mln for failing to address different defects which have been linked to 13 deaths.

That was the maximum allowed by U.S. law and it was the single highest civil penalty ever levied as a result of a recall investigation.

The recalls have already cost the company $1.3bn in the first three months of the year and it now estimates it will cost the firm around $400mln in the April to May period. It expects an internal investigation about the issue to conclude within the next two weeks.

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