WPP, the world's biggest advertising company, said it had seen strong trading in January after reporting 2014 results broadly in line with forecasts due to strong growth in all regions. 

The British group, owner of the JWT and Ogilvy & Mather agencies, said like-for-like net sales in January were up 3.9%, ahead of the 3.3% growth it recorded for the full 2014 year. 

Its underlying growth was helped by estimated net new business billings of £5.8 billion in the year, which put WPP at the top of the net new business tables for the third year in a row. 

The firm, run by the high profile businessman Martin Sorrell, said it had also won a lot of assignments from existing and new clients that would be felt in its 2015 group revenue. 

For 2015, it said it would target net sales growth of over 3% and an improvement in its headline operating margin target of 0.3 margin points. 

For January it said all regions, except Latin America, were up, with Asia Pacific and Africa and the Middle East up well above the average.