The European Union (EU) will not deploy an observer mission for Uganda's presidential election in January, an official said on Monday, after complaints that advice from previous observers to make the polls fair went unheeded.

In the January 14 vote, President Yoweri Museveni, 76, will face off against youthful pop star and lawmaker Robert Kyagulanyi, widely known by his music moniker Bobi Wine and who is seen as the incumbent president's closest competitor.

In the same election, voters will also pick their lawmakers.

"An EOM (election observer mission) will not be present in Uganda in 2021," Attilio Pacific, EU ambassador and head of delegation to Uganda, told Reuters in an email.

He said in taking a decision not to send observers, the EU had considered whether Uganda had "made progress on recommendations provided by previous EU electoral missions."

The EU typically sends the largest team of any similar blocs - a total of 94 monitors were sent at the last poll - and they have stayed in the country sometimes for up to three months.

According to an EU 2018 report, none of the 30 recommendations made by the observer mission sent to monitor the last election in 2016 was implemented.

The recommendations included reforms to make the poll body more independent, elimination of excessive use of force by the armed forces and more transparency in tallying.

Government spokesperson Ofwono Opondo and Museveni's spokesperson, Don Wanyama, were not immediately available for comment.

"What the EU observers do is to add an international flavour of scrutiny, that element now will not be there in 2021," said Chrispin Kaheru, a Kampala-based political analyst.

Wine has complained of harassment and intimidation by security forces.

On the day he was nominated, he was briefly detained after police and military personnel broke his car windows and forcefully removed him.