He said no country alone can meet that challenge, hence the effort must be a united action conducted in accordance with each country’s economic and technological capabilities. Donald Tusk stressed, however, that the program must be constructed in such a manner as to guarantee the individual country’s development in a manner suitable to its economic realities. He reminded that in Poland’s case the principle energy generation resource remains hard coal. Therefore, Poland will strive to upgrade this type of technology to make the process as environmentally clean as possible, PM Tusk declared.