( CNN ) -- Malaysia 's opposition leader has urged his supporters to wear black at a rally to be held in the capital Kuala Lumpur on Wednesday to protest Sunday 's vote , which he claims `` was marred with unprecedented election fraud . '' `` Our conscience can not allow us to accept election results conjured through frauds and cheating . A fight for clean and fair election remains the single most important fight that any Malaysian should relate to , '' Anwar Ibrahim said in a statement released Monday . Prime Minister Najib Razak , the leader of the Barisan Nasional coalition that has ruled for 56 years , took his oath of office on Monday after winning 133 out of 222 parliamentary seats , Malaysia 's national news agency Bernama reported . Anwar 's Pakatan Rakyat coalition won 89 seats , handing Barisan Nasional its worst ever electoral showing . A government spokesperson said on Tuesday that allegations of fraud in the election process were `` unsubstantiated '' and the government 's victory was in line with independent polling . `` Anwar claimed the only way he could possibly lose was if there was 'massive fraud ' , '' the spokesperson said in a statement . `` This is entirely contrary to pre-election opinion polls , including those by Pew Research and the Merdeka Center , which showed significant support for both the Prime Minister and his ruling party and suggested they were on track for a victory . '' The weeks leading up to Sunday 's election saw reports of firebombs , texted death threats and beatings and there were widespread reports that indelible ink used to mark the fingers of advance voters was washing off . Other allegations surfaced on polling day , with Anwar 's party and election observers alleging the government exchanged cash for votes and flew in foreigners to cast their ballots in favor of Barisan Nasional -- a charge denied by the government . `` We were told that 40,000 foreigners were being flown across Malaysia to vote . However , passenger manifests prove that a few hundred Malaysian citizens were flown to their home states , entirely legally , '' it said in a statement . Investors reacted favorably to the election outcome , sending Malaysia 's stock index up more than 8 % on Monday and strengthening the currency . Liam Hanlon , senior political analyst at Cascade Asia Advisors , said the government should interpret its reduced margin of victory as a warning from voters that reform is needed . `` The government must heed this warning and understand that it needs to be more forward-looking in order to survive , '' he said . `` It would be a shame if the opposition 's strong showing actually propelled the country back into more pronounced race-based policies . '' In the 1970s , Malaysia introduced policies that effectively split the country along ethnic lines , giving preferential treatment to the so-called Bumiputera , or ethnic Malays and natives of Sarawak and Sabah . According to the CIA Factbook , just over 50 % of the country is Malay . Chinese make up 23.7 % and Indians 7.1 % . Anwar appealed to voters with a promise to change race-based policies to make them more inclusive and needs-based . James Chin , a professor of political science at the Malaysian campus of Australia 's Monash University , said the results showed that Malaysia 's ethnic Chinese population had voted in a bloc against the government for the first time . He added that some urban Malays had also voted for the opposition . He said that Anwar 's efforts to address election irregularities would depend on whether he drew support from across Malaysia 's multi-ethnic population . `` Elections in Malaysia have never really been free and fair but the big difference this time was for the first time in Malaysian history , the Chinese on both sides of the South China Sea voted together against the government , '' he said , referring to Peninsular Malaysia and Malaysian Borneo . `` The key to tomorrow 's attendance is to see if the Malays are willing to come out . If only the Chinese come out it will look like a racial protest . It needs to be a multiracial protest if it 's going to have any effect . ''
Malaysia 's opposition leader calls on supporters to attend rally on Wednesday . Anwar Ibrahim says Sunday 's poll marred by unprecedented fraud . Election was won by ruling coalition , extending its 56 years in power . A government spokesperson says allegations of fraud unsubstantiated .