Indonesian President Joko Widodo has defended his decision to reject clemency for drug smugglers on death row, but says he is open to abolishing the death penalty if the Indonesian people wanted change.

In an exclusive one-one-one interview with Al Jazeera correspondent Step Vaessen, set to air at 04:30GMT on Saturday, Widodo said "as a human being I feel it too" when asked about the executions which are set to take place soon.

But he said he also felt the "suffering of those parents whose children are addicted to drugs".

The planned executions of Australians Myuran Sukumaran, 33, and Andrew Chan, 31, have sparked diplomatic tension between the two neighbours after Australia's repeated pleas for mercy on their behalf.

The two men, who were convicted of drug smuggling in 2005, are part of a group of up to 11 convicts, mostly foreigners, due to be executed on the prison island of Nusakambangan. A date for the executions has not been announced.

Widodo explained his decision for rejecting the drug smugglers' appeals for clemency, saying that he was not swayed by the nationality of the convicts, nor the lobbying of their country's government.

"I believe the Indonesian legal system is thorough in these cases and looks at the evidence," he told our correspondent.

"When I rejected clemency I took into consideration how many drugs they smuggled, how many pills they distributed.... The court has sentenced them and we cannot discriminate between countries."

'Millions in rehab'

Widodo said there were currently 4.5 million people in drug rehabilitation programmes, including "at least 1.5 million people who cannot be cured".

"This is the picture of Indonesia’s future, our next generation. We want to send a strong message to drug smugglers that Indonesia is firm and serious in tackling the drug problem and one of the consequences is execution if the court sentences them to death," he said.

"Most importantly, our diplomats can explain to other countries the urgency of our drug problem in Indonesia. Explain to them about the conditions here, that drugs are entering villages, ruining our young ones, are being sold at campuses, even universities have drug problems. This is an emergency."

Despite his strong defence of the decision to execute the two Australians and other drug smugglers, Widodo said he would continue to lobby foreign governments to save Indonesian citizens from the death penalty when convicted of crimes overseas.

“As a head of state of course I’m going to try to save my citizens from execution," he said.

"That’s my obligation as a president, as a head of state....To protect my citizens who are facing the death penalty but on the other hand we have to respect other countries that apply capital punishment....

"The constitution and the existing law still allows the death penalty. But, if the Indonesian people want to change it in the future, then it’s possible, why not?"

Indonesian President Joko Widodo's full interview on Talk to Al Jazeera will be broadcast at 04:30GMT on Saturday March 7.