Question: What British Politician, who was the Prime Minister of the Unted Kingdom, was the person who forced a resignation from PAtrick Mercer?

Context articles: Josip Manolić
David Cameron
Patrick John
Edward Lowassa
Prime Minister's Resignation Honours
Patrick Mercer
George Matanzima
Maatia Toafa
James Callaghan
Naoto Kan

Josip Manolić (] ; born 22 March 1920) is a Croatian politician and former high-ranking official of the State Security Administration (UDBA or UDSA) who was the Prime Minister of Croatia from 24 August 1990 to 17 July 1991.
 Croatia formally declared independence during his term, on 25 June 1991.
 Having taken office as Prime Minister at the age of 70 and having left the office at the age of 71, he is the oldest person to date to have served as Prime Minister of Croatia.
 Manolić is also the oldest currently living former prime minister at the age of and the longest-lived holder of the office.
 Following his brief term as Prime Minister he served as the first Speaker of the Chamber of Counties, the upper house of the Croatian Parliament, from 1993 until 1994.
David William Donald Cameron ( ; born 9 October 1966) is a British politician who was Prime Minister of the United Kingdom from 2010 to 2016 and Leader of the Conservative Party from 2005 to 2016.
 He was Member of Parliament (MP) for Witney from 2001 to 2016.
 Cameron identifies as a One-Nation Conservative, and has been associated with both economically liberal and socially liberal policies.
Colonel Patrick Roland John (born Roseau, 7 January 1938) was the Prime Minister of Dominica as well as the Premier of Dominica.
 During his premiership Dominica gained independence from the United Kingdom and he became the first Prime Minister of Dominica.
 He was leader of the Waterfront and Allied Workers' Union and mayor of Roseau before being elected to the legislature in 1970.
 He took on prime ministerial duties in 1974 following the resignation of Edward Oliver LeBlanc.
 After mass protest forced him to resign, John unsuccessfully attempted to overthrow the government of Prime Minister Eugenia Charles with the backing of white supremacist groups (in what became dubbed "Operation Red Dog").
 As a result, he was jailed for twelve years, of which he served only five years.
Edward Ngoyai Lowassa (born August 26, 1953) is a Tanzanian politician who was Prime Minister of Tanzania from 2005 to 2008, serving under President Jakaya Kikwete.
 Lowassa has gone into record as the first Prime Minister to have been forced to resign by a fraud scandal in the history of Tanzania.
 Following his resignation President Kikwete was obliged to dissolve his cabinet as required by the Constitution and with minimum delay, constituted a new one under a new Prime Minister, Mizengo Pinda.
The Prime Minister's Resignation Honours in the United Kingdom are honours granted at the behest of an outgoing Prime Minister following his or her resignation.
 In such a list, a prime minister may ask the monarch to bestow peerages, or lesser honours, on any number of people of his or her choosing.
 For example, in the 1997 Prime Minister's Resignation Honours, an additional 47 working peers were created at the behest of the three main parties.
Colonel Patrick John Mercer, OBE (born 26 June 1956) is an author and former British politician.
 He was Conservative shadow homeland security spokesman before being forced to resign by David Cameron in 2007 for making "unacceptable" racist remarks in an interview with "The Times".
 He was elected as a Conservative in the 2001 general election, until resigning the party's parliamentary whip in May 2013 following questions surrounding paid advocacy, and was an Independent MP representing the constituency of Newark in Parliament until his resignation at the end of April 2014 after the Standards Committee suspended him for six months for "sustained and pervasive breach of the house's rules".
Chief George Mzivubu Mathanzima (26 December 1918 in Qamata – 10 November 2000) was a leader of the Transkei bantustan in South Africa.
 He and his brother, Kaiser co-founded and led the Transkei National Independence Party.
 George Matanzima was appointed as Prime Minister of Transkei after his brother became President.
 George Matanzima served as Prime Minister from 20 February 1979 to 24 September 1987.
 Bantu Holomisa forced the resignation and then the exile of Matanzima in October 1987.
 Stella Sigcau became Prime Minister, but Holomisa soon forced her out of office also and took power himself in December 1987.
Maatia Toafa OBE (born 1 May 1954) is a Tuvaluan politician, representing Nanumea who served two non-consecutive terms as Prime Minister of Tuvalu.
 He first served as Prime Minister from 2004 to 2006, from the resignation of his predecessor, Saufatu Sopoanga, until the defeat of his Cabinet in the 2006 general election.
 He was re-elected to parliament in the 2010 general election; and regained the premiership on 29 September 2010; however he lost the support of the parliament following a motion of confidence on 21 December of the same year.
 On 5 August 2013 Toafa became the Minister of Finance and Economic Development in the government of Prime Minister Enele Sopoaga.
 He was appointed as Deputy Prime Minister following the Tuvaluan general election, 2015.
Leonard James Callaghan, Baron Callaghan of Cardiff, {'1': ", '2': ", '3': ", '4': "} (27 March 1912 – 26 March 2005), often known as Jim Callaghan, was a British politician who served as Prime Minister of the United Kingdom from 1976 to 1979 and Leader of the Labour Party from 1976 to 1980.
 Callaghan is to date, the only British politician in history to have served in all four of the "Great Offices of State", having been Chancellor of the Exchequer from 1964–67, Home Secretary from 1967-70, and Foreign Secretary from 1974, until his appointment as Prime Minister in 1976.
 As Prime Minister, he had some successes, but is mainly remembered for the "Winter of Discontent" of 1978–79.
 During a very cold winter, his battle with trade unions led to massive strikes that seriously inconvenienced the public, leading to his defeat in the polls by Conservative leader Margaret Thatcher.
Naoto Kan (菅 直人 , Kan Naoto , born 10 October 1946) is a Japanese politician, and former Prime Minister of Japan.
 In June 2010, then-Finance Minister Kan was elected as the leader of the Democratic Party of Japan (DPJ) and designated Prime Minister by the Diet to succeed Yukio Hatoyama.
 Kan was the first Prime Minister of Japan since the resignation of Junichiro Koizumi in 2006 to serve for more than 1 year, with predecessors Yukio Hatoyama, Tarō Asō, Yasuo Fukuda, and Shinzō Abe either resigning prematurely or losing an election.
 On 26 August 2011, Kan announced his resignation.
 Yoshihiko Noda was formally appointed as Prime Minister on 2 September 2011.
 On 1 August 2012, United Nations Secretary-General Ban Ki-moon announced Kan would be one of the members of the UN high-level panel on the post-2015 development agenda.