A Dutch Roman Catholic bishop has called for the Catholic tradition of eating fish on Friday to be restored, as a contribution to the fight against climate change.

Speaking on a Catholic current affairs programme on public service TV, Bishop Gerard de Korte said a meat-free day a week would make a huge contribution to cutting CO2 emissions.

The Bishop of Groningen made his suggestion on Sunday, as more than nine hundred churches in the Netherlands rang their bells to urge world leaders to reach an effective treaty at the climate summit in Copenhagen. “We know that every kilogram of meat takes a vast amount energy to produce and causes a great deal of CO2 emissions,” he said. The bishop’s idea gives a religious twist to singer Paul McCartney’s campaign for a meat-free Monday.

Friday is traditionally a day of fasting in the Catholic Church, with fish replacing meat as the dish of the day. In 1989 the Dutch bishop’s conference decided that it was sufficient to eat frugally on a Friday rather than abstaining from meat entirely. However, Bishop De Korte says for environmental reasons it would be better to re-establish Friday as a meat-free day.