Deputy Prime Minister Louis Grech will not be contesting the general election but will remain a consultant if Labour wins another term of office.
Prime Minister Joseph Muscat said when speaking this evening that this was an emotional moment, and said that Mr Grech, 70, would continue attending Cabinet as "he still has a lot to give".
Speaking at a Labour activity in Iklin, Mr Grech said he felt privileged to have formed part of this administration, describing it as "family".
Referring to Dr Muscat as "Ġus", he said he knew it was time for him to close this chapter of his life.
He thanked the prime minister for the opportunity to serve for these four years, prompting a standing ovation.
Mr Grech entered the political fray in 2004 as an MEP and was appointed Labour deputy leader shortly before the 2013 general election when Anġlu Farrugia resigned. He was then made deputy prime minister.
He was among Air Malta's founding officials in 1973 and eventually served as its chairman before becoming a politician.