KUALA LUMPUR (Reuters) - Malaysia's Prime Minister Najib Razak announced on Friday the dissolution of parliament, paving the way for a general election in which he faces an unprecedented challenge from his former mentor turned opposition leader Mahathir Mohamad.
Najib is under pressure to deliver a convincing victory for his undefeated Barisan Nasional (BN) coalition, as he grapples with financial scandals at a state-owned fund and a government palm oil agency, and with public anger over rising prices.
Najib's coalition is still widely expected to win the election despite the scandals, but a significant loss of seats to the opposition could leave the prime minister open to a leadership challenge within his United Malay National Organisation (UMNO) party.
Below is a summary of the electoral process and key facts about Malaysia:
The Election Commission (EC) is expected to meet in the next few days to decide on the dates for the nomination of candidates and for polling across the country's 13 states.
Polling must be held within 60 days of the dissolution of parliament, with a minimum of 11 days of campaigning.
There are about 14 million registered voters. Polls are completed in one day with the result announced the following day.
Malaysia adopted a Westminster parliamentary model after gaining independence from Britain in 1957. The government is elected through a first-past-the-post or simple majority system.
The UMNO-led coalition has been undefeated since independence. The coalition contains parties representing the country's three main ethnic groups: majority Malays, most of whom are Muslim, ethnic Chinese and ethnic Indians.
The opposition has accused the government of gerrymandering, rigging and propaganda through state-controlled media to secure a victory in every election. The government has denied those accusations.
Critics have also said the Election Commission favors the ruling party. The commission has repeatedly denied that.
Campaigning is usually restricted to about two weeks. It begins immediately after the process of nominating candidates is completed, and ends 24 hours before polling day.
There are no publicly telecast debates between candidates. Campaigning is mostly through public gatherings, rallies and visits by candidates to towns and villages.
The general election is for all 222 seats of parliament's lower house, known as the Dewan Rakyat.
Najib's ruling coalition won 133 seats to win the last general election, in 2013, despite losing the popular vote.
The opposition coalition is hoping it can whittle down BN's seat count to gain at least 112 seats - which would give it the right to form a government.
The 70 members of parliament's upper house, known as the Dewan Negara, are appointed, not elected.
GEOPOLITICAL HOT SPOT
Malaysia is a major exporter, its economy driven by oil and gas, palm oil and electronics.
Part of the South China Sea lies between east and west Malaysia, a maritime region that falls within an area claimed by China, and delineated by a "nine-dash-line" on its maps.
Malaysia - and several other countries in the region - have disputed China's claim over the South China Sea, through which about $5 trillion in trade passes annually.
(Reporting by Joseph Sipalan; Editing by Robert Birsel)