Cellphone maker Sony Ericsson unveiled on Thursday two handset models it said are more eco-friendly, adding that the company will push greener features across its product line in the next two years.

The new models, C901 GreenHeart and Naite, will be sold in smaller packages and have user manuals that are electronic. The devices use more recycled materials and consume less energy.

"Today we are announcing ... a commitment to roll out these innovations across the broader portfolio in 2010 and 2011," Sony Ericsson Chief Executive Hideki Komiyama said in a statement.

The role of greener products is increasing rapidly in the cellphone industry, with a recent ABI Research survey saying nearly half of U.S. consumers are likely to be influenced by suppliers' green credentials when purchasing devices.

Sony Ericsson said on Thursday it targets a cut of 20 percent of its carbon dioxide emissions by 2015.

The handset industry is closely followed by environmental organizations around the world due to its large scale. More than 1 billion phones are sold globally each year, which requires the use of sales boxes, add-ons and tons of rare raw materials.

The world's top cellphone maker, Nokia, started to renew its packaging in 2006, and has said it saved 100 million euros ($142.9 million) in less than a year.

Sony Ericsson said its new models will use at least 50 percent recycled plastics — similar to Nokia's 3110 Evolve model, which the Finnish firm introduced last year.

Last year Nokia's chief executive, Olli-Pekka Kallasvuo, showed a prototype of a phone made fully of recycled materials at the Mobile World Congress trade show, but the model has not reached production.

Money-losing Sony Ericsson, the world's fifth-biggest handset maker, is in need of new models to renew its offering since the appeal of the years-old Sony-branded Cybershot cameraphones and Walkman music phones has faded.