The UN rights body on Friday criticised Kuwait and several countries in Asia for resuming executions after halting the practice for several years.
"We are deeply concerned that a number of countries in the Middle East and Asia have recently started reapplying the death penalty after several years of moratorium," OHCHR spokesman Rupert Colville told reporters in Geneva.
He criticised Kuwait, India, Indonesia and Japan for resuming executions in a move that he said flies in the face of "the overwhelming global trend towards abolishing the death penalty."
Kuwait on Monday carried out its first executions in six years, hanging a Saudi, a Pakistani and a stateless Arab who had been convicted of murder.
And in Asia, India resumed executions late last year after an eight-year moratorium, and Japan also applied the death penalty for the first time in nearly two years.
Last month, Indonesia carried out its first execution in four years.
Of the countries that never stopped carrying out the death penalty, like Saudi Arabia, Yemen, Iran, China and North Korea, Colville expressed particular concern about the soaring number of executions in Iraq.
At least 12 people had been executed in the country so far this year, he said, while 123 people, including five women, were executed there in 2012.
That "was a massive increase over previous years, and deeply worrying in a country where there are persisting serious concerns about compliance with fair trial standards," Colville said.
The United States has meanwhile executed five people so far this year, he said.
"In many cases, the death penalty involves clear violations of international norms and standards," he said, listing for instance the absence of fair trials and due process, executions of juvenile offenders and long waits on death row.
"We appeal to all governments concerned to take necessary measures and establish an official moratorium on all executions with the aim of abolishing the death penalty," Colville said.