Saudi Arabia on Monday reported a sharp drop in executions in 2020, as the kingdom seeks to blunt international criticism of its human rights record.

The Gulf state, an absolute monarchy, has long faced criticism for one of the world's highest rates of executions and what human rights campaigners call an opaque judicial system.

The Saudi government's Human Rights Commission (HRC) said it documented 27 executions in 2020, a decrease of 85 percent over the previous year due in part to a moratorium on the death penalty for drug-related offences.

"The Commission welcomes this news as a sign that the kingdom and its justice system are focusing more on rehabilitation and prevention than solely on punishment," HRC president Awwad Alawwad said in a statement.

"The moratorium on drug-related offences means the kingdom is giving more non-violent criminals a second chance."

Saudi Arabia put 184 people to death in 2019, according to Amnesty International, which said it was the highest number ever recorded in a single year in the kingdom.

Britain-based campaign group Reprieve reported 25 executions in Saudi Arabia in 2020, saying it was the lowest figure since it began monitoring executions in 2013 but cautioned that the number could increase this year.

"The decline can partly be attributed to the Covid-19 lockdown from February to April, when the government carried out no executions due to restrictions to control the virus," Reprieve said in a statement.

"However, there is reason to believe that the number of executions will rise in 2021. 

"The government recommenced executions at an increased rate in the final quarter of 2020: approximately one-third of all executions last year were carried out in December alone."

Monday's announcement by the HRC follows a string of judicial reforms in 2020.

Last April, the HRC said the kingdom was ending the death penalty for those convicted of crimes committed while aged under 18.

Citing a royal decree, the HRC said individuals convicted as minors would receive a prison sentence of no more than 10 years in a juvenile detention facility.

Last April, the HRC also announced Saudi Arabia was abolishing court-ordered floggings, in a move welcomed by campaigners.

The changes underscore a push by de facto ruler Crown Prince Mohammed bin Salman to modernise the ultra-conservative kingdom, long associated with a fundamentalist strain of Islam.

Activists, however, are sceptical that the reforms will see political prisoners released or pause a sweeping government crackdown on dissent.