DAKAR (Reuters) - Senegal’s two best known opposition figures have been barred from running in presidential elections next month, the Constitutional Council said on Monday, increasing President Macky Sall’s chances of securing a second term in office.

FILE PHOTO: Senegal's President Macky Sall speaks at the 2018 Beijing Summit of Forum on China-Africa Cooperation joint news conference at the Great Hall of the People in Beijing, China September 4, 2018. Lintao Zhang/Pool via REUTERS/File Photo

Khalifa Sall, a former mayor of Dakar who bears no relation to President Sall, and Karim Wade, the son of former President Abdoulaye Wade, were jailed for graft and corruption in 2018 and 2015 respectively.

Under Senegalese law, the sentences effectively ended their chances of running in the Feb. 24 poll and the Constitutional Council confirmed this outcome on Monday.

The opposition says the sentences were part of the president’s plan to silence popular opponents so he can secure a second mandate, charges the ruling party denies.

Both presidential hopefuls had collected more than the 53,000 supporting signatures required to run.

Khalifa remains in jail, where he is serving a five-year sentence for embezzling 1.8 billion CFA francs ($3.2 million) in public funds. He was denied an appeal by the Supreme Court earlier in January, but his lawyer plans to take the case to another chamber of the court.

Karim went into exile in Qatar in 2017 after serving half of his six-year sentence.

In a document sent to lawyers and seen by Reuters on Monday, the Constitutional Council said Khalifa and Karim’s candidacies went against Senegal’s electoral law, which bars citizens sentenced to more than five years in prison from running for president.

The two have 48 hours to appeal the Council’s decision, which will publish a final list of approved candidates 35 days before the poll.

Only four opposition candidates have so far been approved by the Council, including Wade’s former Prime Minister Idrissa Seck. Political neophyte Ousmane Sonko is popular among Senegalese youth, which represent a significant portion of the voting population.

Senegal, a major exporter of fish and peanuts, has had three largely peaceful transitions of power since independence from France in 1960.