The by-election to select a new MP for Parekura Horomia's electorate will be held on June 29.
Horomia died on April 29 and his funeral was held last week.
Prime Minister John Key today announced the by-election in the eastern Maori seat of Ikaroa-Rawhiti would be held on the last Saturday in June.
“I have been advised that, since the vacancy arising from Mr Horomia’s death has now been gazetted, it is appropriate to set a date for the by-election," he said.
Candidate nominations must be with the Electoral Commission by midday on June 5.
National will not stand a candidate in the by-election.
Labour today opened nominations for its candidate and the Maori and Mana parties were also expected to stand.
Labour president Moira Coatsworth said a number of talented men and women had already contacted the party about standing.
"Parekura was a dedicated politician of the people, and we intend to run a process which he would be proud of, and select a candidate who is a worthy successor to him.”
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