The 4,700 posters for Portuguese olive oil brand Oliveira Da Serra were created by McCann Erikson Portugal and ran across sites from all of the country's site owners including JCDecaux, Cemusa, MOP and APS.

The paper was Austrian mill Lenzing's City Light Offset FSC Mixed 50%, a 150gsm 50:50 mix of FSC certified and recycled fibre, and the job was produced on the firm's Manroland 900 XXL press.

"We are very green, so when Lenzing suggested using this paper we were very keen to go ahead," said Impression Portugal chief executive Pedro Jacques de Sousa. "We are constantly innovating and looking at our environmental credentials and we were the first Portuguese printer to gain the Ambigraf environmental certification from the Portuguese national graphics association Apigraf."

De Sousa added that the firm was planning to use more recycled paper, and was working with Lenzing to the 135gsm weight of the same grade for rolling systems.

The firm's switch to recycled paper posters follows from its adoption last year of high definition outdoor (HDO) one-piece polyester billboards, in conjunction with JCDecaux.

He added Portugal was only the second country in Europe after the UK to adopt HDO, and as well as having environmental benefits the high image quality had attracted high-end brands "breathing new life into billboards".