It is illegal to use, produce, transfer or stockpile cluster bombs, since the coming into force of the UN Convention on Cluster Munition on 1 August 2010. This treaty is international law and although Saudi Arabia has neither signed nor ratified it, the UK ratified this treaty in 2010, meaning it is not only illegal for the UK to produce and transfer cluster bombs according to British as well as international law, but the country also has a duty to promote the aims and ratification of the treaty to non-signatory states. In January 2017, Parliament debated a motion calling for an independent investigation into violations of International Humanitarian Law in Yemen. Incidents to be investigated include the bombing of a funeral which killed 140 people; the bombing of a refugee camp and eight bombings of densely populated areas in Sa'dah, Sana'a, Hodeidah, Hajjah and Ibb, which Amnesty International have raised concerns about. In a 20 June 2019 judgment, the Court of Appeal ruled favoring the anti-arms-trade campaigners in their legal fight against the government over their support of the Saudi-led conflict in Yemen. The Campaign Against Arms Trade (CAAT) asserted that the fighter jets and bombs supplied by the government of UK are being used by the Saudi-led coalition in the killing of civilians and abusing international law. International trade secretary, Liam Fox, said that the government would challenge the judgment, but had adjourned any licences for the Saudi government and its partners in the coalition. At the June 2019 G20 Summit held in Osaka, Japan, UK Prime Minister Theresa May urged the Crown Prince of the Kingdom of Saudi Arabia to collaborate with the United Nations to find a solution to the 4-year long conflict in Yemen. Labour Party leader, Jeremy Corbyn, claimed that the Prime Minister wasn't successful in signalling the UK government's disapproval of Saudi's role in Yemen war. He added, "She should confirm the UK government will immediately stop selling arms to his regime." Andrew Smith, of Campaign Against Arms Trade (CAAT), said that Jeremy Hunt and Boris Johnson "have played an utterly central and complicit role in arming and supporting the Saudi-led destruction of Yemen." Jeremy Hunt's Conservative leadership campaign was partly funded by Ken Costa, investment banker with close ties to Saudi Arabia's Crown Prince. On 14 February 2012, a Saudi 70-year old called Ali Mohammed Baqir al-Nimr was arrested after taking part in anti-government rallies in Saudi Arabia. In 2014, he was sentenced to death and pro-Saudi government media reported that Nimr would be crucified.