Sri Lankan President Maithripala Sirisena last week announced an end to a moratorium on the death penalty that has been in force in the South Asian country since 1976. The president also said he had signed the death warrants for four drug convicts and they would be executed soon.

Sirisena's office has said the president wanted the hangings to send a powerful message to anyone engaged in the illegal drugs trade. Sri Lanka has been grappling with drug-related crimes for years and the country is believed to be a transit hub for drug peddlers.

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The decision to reinstate capital punishment, however, has been criticized by human rights groups as well as the international community.

Sirisena said Monday he had rejected a telephone appeal by UN Secretary General Antonio Guterres to reconsider his push to reintroduce the death penalty.

Sirisena also accused the European Union of interfering in the internal affairs of his country, saying that EU diplomats had threatened him with tariffs if Sri Lanka went ahead with the executions.

Sirisena's decision to reinstate capital punishment has been slammed by the human rights groups

In a DW interview, Meenakshi Ganguly, South Asia director at Human Rights Watch, said that the alleged deterrent effect of the death penalty has been repeatedly debunked.

DW: What are your views on the Sri Lankan government's move to end a moratorium on the death penalty?

Meenakshi Ganguly: Sri Lanka's decision to issue death warrants is extremely disturbing. Human Rights Watch opposes the death penalty because it is inherently cruel. Sri Lanka, with a 43-year de facto moratorium, was an example to others. It is unfortunate that even as many other nations are committing to abolish the practice, the Sri Lankan government has chosen to be regressive. We hope that the government will revoke the death warrants, reinstate the moratorium on capital punishment, and take steps to abolish it altogether.

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Some say the decision to reinstate capital punishment after over 40 years of moratorium was an electoral gambit, aimed at boosting Sirisena's chances of reelection as president. What's your take on this?

Apart from the fact that the death penalty is inhumane, it is also irreversible. To reinstate the practice, if motivated by a political calculus, is particularly irresponsible. President Sirisena renewed calls for the death penalty following a visit to the Philippines in January, during which he called President Rodrigo Duterte's "war on drugs" an "example to the world." A decision to restore the death penalty because he was inspired by the Philippines' murderous "drug war" may be the worst possible justification and a violation of international law.

Ganguly: 'Apart from the fact that the death penalty is inhumane, it is also irreversible'

President Sirisena has signed death warrants for four drug offenders and says he wants the hangings to send a powerful message to anyone engaged in the illegal drugs trade. Is this the right way to go about tackling illegal drugs?

Where the death penalty is permitted, international human rights law limits the death penalty to "the most serious crimes," typically crimes resulting in death or serious bodily harm. The UN Human Rights Committee and the special rapporteur on extrajudicial, summary, or arbitrary executions have concluded that the death penalty for drug offenses fails to meet the condition of "most serious crime." In September 2015, the UN high commissioner for human rights reaffirmed that "persons convicted of drug-related offences … should not be subject to the death penalty."

How do you think the death penalty will affect Sri Lanka's relations with the international community?

The decision to reverse its moratorium on capital punishment will disappoint many of Sri Lanka's friends in the international community. The United Nations General Assembly has continually called on countries to establish a moratorium on the death penalty, progressively restrict the practice, and reduce the offenses for which it might be imposed — all with a view toward its eventual abolition.

Will diplomatic appeals help prevent executions in Sri Lanka?

We hope that the government will heed calls from human rights activists at home and abroad, as well as its friends in the international community.

What can human rights groups do to persuade the Sri Lankan government to change its course?

President Sirisena believes that his decision will be popular because he is acting against drug traffickers, but he needs to understand that the alleged deterrent effect of the death penalty has been repeatedly debunked. Instead Sri Lanka should take into account the UN Office on Drugs and Crime which has called for an end to the death penalty and specifically urged member countries to prohibit use of the death penalty for drug-related offenses, while urging countries to take an overall "human rights-based approach to drug and crime control."

Meenakshi Ganguly is South Asia director at Human Rights Watch.

The interview was conducted by Srinivas Mazumdaru.