The Federal Government of Belgium (, , ) exercises executive power in the Kingdom of Belgium. It consists of ministers and secretary of state ("junior", or deputy-ministers who do not sit in the Council of Ministers) drawn from the political parties which form the governing coalition. The federal government is led by the Prime Minister of Belgium, and ministers lead ministries of the government. Ministers together form the Council of Ministers, which is the supreme executive organ of the government (equivalent to a cabinet). Formally, executive power is vested in the king, who formally appoints the ministers. However, under the Constitution of Belgium, the king is not politically responsible for exercising his powers, but must exercise it through the ministers. The king's acts are not valid unless countersigned by a minister, and the countersigning minister assumes political responsibility for the act. Thus, in practice, the ministers do the actual day-to-day work of governing. Function and composition At the federal level, executive power is wielded by the federal government, whilst the prime minister is the head of the government. Each minister heads a ministry, and secretaries of state, who are deputy to a minister, help run these ministries. The government reflects the weight of political parties that constitute the current governing coalition for the Chamber. No single party or party family across linguistic lines holds an absolute majority of seats in Parliament. Under current practice, no party family can win enough seats to govern alone, let alone win a majority. The number of ministers is limited to 15, equally divided between French-speaking and Dutch-speaking ministers, according to Article 99 of the Constitution. Although the prime minister is officially exempt from this quota, no francophones held the post from 1979 to 2011. Some of the ministers are also deputy prime ministers; but in addition to taking the position of acting prime minister, they are also the link between the government and their political parties. A deputy prime minister is the voice of their political party within the federal government, and is also the voice of the federal government within their political party. Government meetings are conducted through simultaneous interpreters. The prime minister and his ministers administer the government and the various Federal Public Services (, ; roughly equivalent to ministries in other countries' administrative organization). As in the United Kingdom, ministers must defend their policies and performance in person before the Chamber.