The Carter Centre on Monday asked President Uhuru Kenyatta to initiate a sustained national dialogue to heal the wounds aggravated by the often tense and tumultuous electoral period.
The observer team also told all parties in the contest to accept the Supreme Court's unanimous decision to uphold the October 26 election results.
This followed the decision of the court led by Justice David Maraga which said Uhuru was validly elected during the repeat presidential vote.
NASA leader Raila Odinga, who was Uhuru's close competitor in the nullified August 8 election, withdrew from the fresh vote.
The Opposition and any reference to it was also expunged from documents of the petition filed by ex-Kilome MP Harun Mwau and that of two voters – Njonjo Mue and Khelef Khalif.
Following the events preceding the Monday declaration, Carter Centre said it is incumbent on political leaders and their supporters to seek common ground going forward.
"President Uhuru Kenyatta, who has a fresh mandate to lead all Kenyans, should re-initiate the national dialogue that culminated in the 2010 Constitution," the observer group said in a statement on Monday.
The team, which was led by ex-US Secretary of State John Kerry during the August 8 election, said the dialogue should deal with ethnic and tribal rifts.
They have proposed that the talks come up with additional measures to address the divisions that are characteristic of Kenya’s politics.
The team added that the conversation should ensure the protection and fulfillment of the rights of all Kenyans.
The Kerry team further advised Kenya to learn that elections in resilient democracies are centred on peaceful competition and the orderly transfer of power.
"They (elections) are not for weakening democratic institutions and life-and-death clashes."
The observer group also warned police against using excessive force against unarmed citizens.
"We remind the Kenyan government of its obligation to protect the constitutional rights of peaceful assembly, free speech, and security of the person, to enable inclusive participation in the country’s political and dialogue processes."
The Carter Center said it has taken note of the violence during demonstrations following Raila's return from the US.
During the welcoming party, a number of people were killed as police attempted to break the crowd that sought to welcome the ODM leader.
A number of businesses were destroyed following the ensuing running battles which lasted for a better part of last Friday.
Carter Center deployed a core team of experts who were monitoring key parts of the electoral process in Kenya since April.
This included voter registration, campaigning, electoral preparations, and the resolution of disputes in the courts but reduced the number ahead of the October vote.
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