Ukraine's presidential elections were honest and transparent, international observers including the trans-Atlantic security body the OSCE said on Monday, praising the polls as an impressive display of democracy.

"The professional, transparent and honest voting and counting should serve as a solid foundation for a peaceful transition of power," the observers said in a joint statement.

The assessment had been anxiously awaited after results showed that pro-Russia candidate Viktor Yanukovich had won the election with a slim lead over his challenger Prime Minister Yulia Tymoshenko.

The observers said the elections met most of Ukraine's OSCE and Council of Europe commitments.

Joao Soares, special coordinator of the OSCE short-term observers said: "Yesterday?s vote was an impressive display of democratic elections. For everyone in Ukraine, this election was a victory."

As well as the OSCE Office for Democratic Institutions and Human Rights, the assessment was made by observers from the European Parliament, the Council of Europe Parliamentary Assembly, the NATO Parliamentary Assembly and the OSCE Parliamentary Assembly.