Sarwar, a close aide of Pakistan's Prime Minister Nawaz Sharif is a former Labour party MP from Glasgow in Scotland. He will now lead over 90 million people in Pakistan's largest province.
Sarwar was forced to renounce his British nationality as Pakistan's law forbids ministers and senior officials from holding dual nationality.
Earlier, Rehman Malik, who was an interior minister in the previous PPP government, had to give up his British nationality to stick to the office.
"It was a difficult decision. My children were raised in Glasgow, my grandchildren are there and I'm going to miss them but sometimes you have to make difficult decisions for the greater good," the 60-year-old MP told 'The Daily Telegraph'.
"People say life begins at 40, but I'll be 61 soon and I believe life begins at 60. I'm going to be working very closely with Gordon Brown (former British Prime Minister and now UN special envoy on education). Both of us will be working on education in Pakistan, on an ambitious plan to put 3.5 million kids into schools over the next three years. It's education, education, education," he added.
Sarwar played a key role in choosing candidates for key constituencies, which paved the way for Pakistan Muslim League(N)leader Nawaz Sharif's election victory earlier this year.
In return, Sharif sought to reward him for his role by inviting him to be his new High Commissioner in London, but Sawar rejected the offer in favour of a return to Pakistan.
"The passion of my life has always been fighting poverty, particularly child poverty, and people in my constituency loved that. What I'm leaving behind is great memories of Scotland, my children being born there, and the respect and honour given to me by the people of Glasgow," said Sarwar
Sarwar's son, Anas Sarwar, who succeeded his father as the MP for Glasgow Central in 2010 and later became deputy leader of Scottish Labour, said, "I am an extremely proud son and we are an extremely proud family. The opportunity for my father to go back to the place where he was born and to give something back to the country is a massive one."
"While he loves Scotland and the UK, he has always had a commitment to his mother country," Anas added.
Mohammed Sarwar was born in Saleempur in Pakistan's Punjab province and moved to Britain in 1978 after studying politics at Faisalabad University. He and his brother set up a Glasgow cash-and-carry business which made him a multi-millionaire.
He won the Glasgow Govan seat in the 1997 election, but was soon suspended and charged with bribing a rival candidate to make a false statement.
He was later acquitted and went on to become chairman of the Scottish Affairs Select Committee before standing down as an MP in 2010.
Photograph: Jeff J Mitchell/Reuters
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