More than 800 extra United Nations police officers will be sent to the Democratic Republic of Congo to help with elections expected next year.
The UN's operation in DR Congo is the biggest in the world
They will join what is already the UN's biggest peacekeeping operation, with almost 19,000 personnel.
The UN Security Council voted for the temporary expansion to ensure the smooth running of the polls.
Elections were due before the end of June under the terms of the 2002 peace deal, but MPs backed a six-month delay.
Implementing a peace deal since the end of a five-year civil war, in which an estimated three million people were killed, has proved difficult.
The planned elections will the be fist since independence from Belgium in 1960.
Registration for the election is under way and an estimated 28 million Congolese will be eligible to vote.