The upper house of Afghan parliament wants a London-based group pushing for the legalisation of Afghanistan's huge opium crop to leave the country, the counternarcotics ministry said Saturday. A meeting of the upper house last week decided the Senlis Council "should stop their activities in Afghanistan and leave this country," the ministry said in a statement. The international think-tank has been pushing for Afghanistan to legalise its opium crop, which supplies up to 90 percent of the heroin used in Europe, saying crop eradication will never work. The group says opium production should be licenced and the crop used to make legal painkillers for developing countries, which it says have a growing demand for these drugs. The upper house said the activities of the Senlis Council were against a ruling by religious leaders against drugs, as well as the constitution, which also prohibits their production and use.