Poland could face legal action and EU penalties for failing to "adequately protect" its natural habitats, a European Commission official has said.

EC biodiversity expert Agata Zdanowicz said Poland had so far failed to comply with the EU's Natura 2000 programme, describing the situation as "serious".

The Commission started an "infringement procedure" against Poland in April. This could lead to a court case and the blocking of EU funds for projects in Poland's environmentally fragile areas. Natura 2000 is an EU-wide programme to safeguard the 25-nation bloc's most important wildlife areas and species.

Half of Europe's mammal species, one-third of reptile, amphibian and fish species, as well as one-third of plant species are threatened with extinction, according to the World Wildlife Fund (WWF). Poland is home to rare species such as bison, wolves, bears and eagles living in river valleys, wetlands and forests.

The Commission rejected Poland's proposals on Natura 2000 earlier this year, describing them as "significantly insufficient".