Indonesia will not allow one of its citizens accused of causing forest fires last year to be "processed" under the laws of Singapore, said its Vice-President Jusuf Kalla.
"If there is an offence, Singapore can take action, but (the offence) occurred in Indonesia, that is the concern," he said on Sunday.
Mr Kalla was referring to Singapore's action against companies responsible for causing the forest fires in Indonesia that led to last year's transboundary haze crisis.
Environment and Forestry Minister Siti Nurbaya Bakar yesterday echoed his sentiments in her response to questions from reporters after a climate change event in Jakarta.
She said the Asean agreement on transboundary haze pollution is a multilateral one, and not a bilateral pact between Singapore and Indonesia.
Thus, "Singapore cannot step further into Indonesia's legal domain", added Ms Siti.
She said Singapore's Transboundary Haze Pollution Act (THPA) remains a "controversial" law that is still being debated among Asean officials from Singapore, Brunei, Indonesia, Malaysia and Thailand. That is why she feels that Singapore's action under the law against errant firms in her country is not a show of "mutual respect" to Indonesia.
"The basic principle of cooperation is that countries should respect each other's sovereignty," she said.
She added that Indonesia is not "keeping still" and has imposed sanctions on firms responsible for fires that led to the haze.
These latest comments come after Singapore's National Environment Agency said last month that it had obtained a court warrant against an Indonesian company director in line with the THPA.
This is after the director had failed to turn up for an interview despite being served a legal notice to explain his firm's measures to tackle fires on its concession land.
Ms Siti had said on May 14 that certain bilateral collaborations with Singapore will be terminated and others subjected to a review.
Singapore's Ministry of the Environment and Water Resources, however, said last week that it has renewed its haze assistance package to Indonesia, which it has been offering since 2005.
Environment and Water Resources Minister Masagos Zulkifli has maintained that Singapore's action has the support of the international community. "We are not doing anything criminal nor wrong. We are just asking for the companies and the directors to own up and be accountable for what they've done."
Indonesia has yet to indicate its acceptance of Singapore's help, but Mr Kalla said his country will accept help if it is really needed and reminded its neighbours that tackling the forest fires is "not as easy as what our friends in Asean think".