BBC said:The party of Kenya's opposition challenger Raila Odinga says he has won his country's presidential election.
Official figures gave Mr Odinga a four percentage point lead over President Mwai Kibaki, with three-quarters of the vote counted.
President Kibaki's party scoffed at the claims, saying it would wait for the official results.
"Any other kangaroo results given by any Tom, Dick or Harry deserve every contempt," said a spokesman.
The head of the country's election commission, Samuel Kivuitu, said that with 159 of Kenya's 210 constituencies tallied, Mr Odinga had 3,726,240 votes, to Mr Kibaki's 3,416,139 - around 49.5% to the challenger and 45.3% to the president.
Mr Kivuitu admitted there had been problems establishing results from some areas.
He warned that "if we don't get the results quickly, we will have to announce what we have".
Mr Odinga's Orange Democratic Movement raised fears that the delay may indicate electoral officials were under pressure to rig the result, and said it was now time for the president to admit defeat.
"In view of the growing anxiety and restlessness in the country over the extended delay... we now call upon the outgoing president to acknowledge and respect the will of the Kenyan people and concede defeat," said Mr Odinga's vice-presidential candidate Musalia Mudavadi.
mwenyekiti wa ECK amesema asipopata matokeo kufikia jioni atatangaza matokeo ya uraisi ya majimbo yale aliopata tu na kutangaza rais. this is from the press conference aliofanya na wandishi wa habari a few minutes ago.
Jamani kura zinataka kuibiwa na pia Mombasa kuna vurugu sasa hivi.
Yaani Afrika tuna matatizo makubwa sana, tunahitaji masaa mangapi kuhesabu kura chini ya 5000 kwenye kituo kimoja?
Who ever becomes the President, it will not be easy for him to rule. Kama Raila akiingia inawezekana asiwe na majority kwenye bunge, same applies to Mwai. Kwa hiyo naona wazi kabisa kuwa come what may itakuwa kazi ngumu kwenye siasa za kenya!
Kinachoshaangaza ni kwamba majimbo mengine ni ya hapo hapo Nairobi! Ndiyo maana ODM wana mashaka sana na hali hiyo. Kama yangechelewa matokeo ya kule kaskazini mashariki watu wangeweza kuelewa.
NAFUATIA NEWS HUKU MSIJALI. ECK CHAIRMAN YUPO HEWANI
mchuzi ulikuwa mzuri na tulianza kuusifu ila sasa wanataka kuuongeza chumvi usilike kwa ubwabwa.
nnakusudia tulikuwa tayari tunausifu uchaguzi wa kenya kuwa the best election ever happened in africa lkn sasa wanataka kuharibu.
Kenyan Tanzania nimesikia kuwa Mwenyekiti amemuita mmoja kati ya wagombea urais kuwa ni sawa na "mtu asiyekuwa na suruali anayejidai kumiliki hoteli kubwa". Kama ni kweli who was he refering to?!
Nakubaliana na wewe, tulisifia mapema. Ila tu, wenzetu wametuzidi sana maana Mwenyekiti wao wa tume ya uchaguzi inaelekea hataki mchezo. Angelikuwa Makame wetu, hapo anatetemeka na kupiga simu za siri Ikulu kuwauliza afanyeje.
Im in kibera right now , its crazy, shops being looted and burnt, panic buying, tear gas kila mahali. But one thing is for sure, people here will not accept rigged elections. Tuombeeini jamani