Made Deputy Prime Minister for Investments in 2016, under Prime Minister Robert Fico, Pellegrini was sworn in as head of government after his predecessor resigned on 15 March 2018 in the wake of the murder of journalist Ján Kuciak. President Andrej Kiska approved of Pellegrini's Cabinet on 21 March 2018; 81 members of the National Council voted in favour of approving the cabinet the next week.