Saudi Arabia executed 170 people in 2023, including four on New Year's Eve -- an increase on the previous year, according to an AFP tally based on announcements by Saudi authorities.
A total of 147 convicts were executed in 2022 in the Gulf state, routinely criticised by human rights activists who condemn its prolific use of capital punishment.
A record of 187 executions took place in the kingdom in 2019.
The four people executed on Sunday had been convicted of murder, the official Saudi Press Agency reported, citing statements from the interior ministry.
They included two in the north-western city of Tabuk, one in the capital Riyadh and one in Jazan in the south-west.
Those executed over the course of 2023 included 33 people accused of terrorism-related crimes and two soldiers convicted of treason.
There were 38 executions in December, the deadliest month.
In 2022, Saudi Arabia executed more people than any other country besides China and Iran, Amnesty International has said.
The kingdom, notorious for beheadings, drew a wave of condemnation from around the world when it executed 81 people in a single day in March 2022.
The authorities deem the executions to be compatible with sharia law, the Islamic law code based on the teachings of the Koran, and necessary to "maintain public order".
De facto ruler Crown Prince Mohammed bin Salman is seeking to transform the world's biggest crude oil exporter into a business and tourism hub.
Yet activists say the kingdom's continued embrace of capital punishment undermines the image of a more open, tolerant society that is central to Prince Mohammed's Vision 2030 reform agenda.