 In 2010 Vassallo joined the Cabinet of European Commissioner John Dalli where he is responsible for animal health and welfare.The appointment came as a surprise considering that Dalli and Vassallo both held very senior positions in rival Maltese parties belonging to different political families.It has been speculated that Dalli wanted Vassallo on his team to make use of his contacts with The Greens–European Free Alliance group in the European Parliament on environmentally-sensitive issues such as animal welfare and genetically modified organisms.