UPDATE 2-Western monitors press Tymoshenko to concede defeat

* OSCE urges Ukraine leaders to peaceful transfer of power

* NATO body, Council of Europe press Tymoshenko to concede

(Recasts, adds further quotes)

By Matt Robinson

KIEV, Feb 8 (Reuters) - International monitors on Monday urged Ukraine's Yulia Tymoshenko to concede defeat to her rival Viktor Yanukovich in Sunday's presidential run-off vote and shake hands with him for the sake of stability.

The election in the ex-Soviet state gave opposition leader Yanukovich a slender win over Prime Minister Tymoshenko, but the latter has refused to concede.

"Yesterday's vote was an impressive display of democratic elections. For everyone in Ukraine, this election was a victory," the observers, headed by the Organisation for Security and Cooperation in Europe, said in a statement.

"It is now time for the country's political leaders to listen to the people's verdict and make sure that the transition of power is peaceful and constructive."

The OSCE verdict was almost tantamount to a call by the world community for Tymoshenko to accept the fight was over.

Adding extra weight to this appeal, Assen Agov, head of the NATO Parliamentary Assembly's delegation, told a news briefing where the report was made public: "Normally for the good of the nation the one who loses shakes hands with the one who wins."

"What is important is that the loser keeps in mind the need for stability in the country," said Matyas Eorsi, head of the delegation of the Council of Europe's Parliamentary Assembly.

Aides of Yanukovich before the OSCE verdict pressed the fiery Tymoshenko to accept defeat, but she remained silent and put off a news conference scheduled for Monday until Tuesday.

Before the runoff, she had threatened to call mass protests against the result if she suspected electoral fraud by her opponent.

Latest official data showed that with 97.93 percent of all votes counted, Yanukovich was leading with a margin of 2.65 percentage points over Tymoshenko.

"The observers ... concluded that the lack of mutual trust between the candidates and the deficient legal framework were at the root of the problems observed and constitute an immediate challenge for the new leadership," the OSCE-led monitors said.