By Susannah Price
BBC UN correspondent
The UN has chosen Argentina, Denmark, Greece, Japan and Tanzania as the five states to become non-permanent members of the Security Council next year.
The new non-permanent members will be able to influence debate
There were only five candidates for the seats which were agreed in advance by regional groupings.
They will take up their posts at the beginning of January for two years.
While non-permanent members do not have a veto, their vote can be crucial because resolutions need nine out of 15 members to vote in favour to be passed.
The new members of the Security Council could have an impact on the atmosphere here during the next year.
Last year, the opposition from several non-permanent members to military action in Iraq helped persuade the US to abandon plans to pass a second resolution giving Iraq a deadline to disarm.
At the end of this year those stepping down will include two of the most vociferous opponents of the war on the Security Council, Germany and Pakistan.
To replace them, Japan, which has non-combat troops in Iraq, and Denmark, which also has soldiers there, will take their seats along with Greece, Tanzania and Argentina.
The contentious issue of the reform of the Security Council will be a key issue next year.
There is widespread support for the expansion of the council, but no agreement as yet to how large it should be, who should get seats, whether they should be temporary or permanent and whether any new members should have the veto.
Japan and another current non-permanent member of the Security Council, Brazil, are both seeking a permanent seat.
The US has backed Japan's candidacy and welcomed its impending arrival on the Security Council.
"Having the second most generous donor nation to the UN on the Security Council is extremely important and it is long overdue that Japan has a say in what the Security Council does," said Richard Grenell, spokesman for the US.
While some expect that next year's Security Council could be less divided, this will entirely depend on what issues dominate the agenda.
Phyllis Bennis of the Institute for Policy Studies in Washington says: "The jockeying for credibility in the Security Council could make members much more eager for collaboration and consensus."
However, alliances and divisions on the Council can change suddenly.
The US and France, divided over Iraq, came together recently to draw up a draft resolution on Lebanon.
And analysts say the atmosphere at the Security Council next year could also depend on the outcome of next month's presidential elections in the US.