SINGAPORE - Agreements on three longstanding, often challenging, issues between Singapore and Indonesia - airspace management, defence cooperation and extradition - have been described as a major step forward for bilateral relations.

At a joint press conference with President Joko Widodo in Bintan on Tuesday (Jan 25), Prime Minister Lee Hsien Loong said the pacts take into account both parties' interests and represent a good balance of benefits.

They are also durable agreements for the long haul, designed to last for at least a generation and create a solid foundation to move relations forward with confidence and trust, he added.

What made the deals possible?

A milestone appears to be the last Leaders' Retreat in Singapore in 2019, when PM Lee and President Widodo agreed on a framework for discussions to resolve the longstanding issues of airspace management and military training.

PM Lee said then: "This framework acknowledges that the core interests and rights of both countries must be recognised and respected."

Mr Joko added: "Indonesia respects the position of Singapore, which understands Indonesia's wish to oversee its own airspace."

They tasked Senior Minister and Coordinating Minister for National Security Teo Chee Hean and Indonesia's Coordinating Minister for Maritime Affairs and Investments Luhut Pandjaitan to arrive at agreements based on this framework, which was expanded last year to include extradition.

How do the deals reflect a balance of benefits for both sides?

They acknowledge both sides' interests, as well as rights.

Take the new flight information region (FIR) agreement.

Under international law, global airspace is divided into FIRs - which don't neatly follow territorial boundaries, but which a number of countries have sought to realign over the years. Countries are responsible for providing flight information and navigation services in their assigned FIRs. The Singapore FIR - which air traffic controllers here have managed since 1946 under international arrangements to ensure aviation safety - currently covers the airspace over the Riau and Natuna Islands.

But Jakarta has been seeking a realignment for some time, leading up to the recent discussions on the subject.

In its negotiations, Singapore has sought to ensure that Changi Airport can continue to safely and effectively provide air traffic control services as an international hub.

The concluded agreement realigns the boundary between the Singapore and Jakarta FIRs, with the airspace over the Riau and Natuna islands to come under Indonesia's charge. But for 25 years - and this can be extended - Singapore has been delegated to provide air navigation services in portions of the airspace within the realigned Jakarta FIR.

Both sides have also worked out arrangements for civil-military cooperation in air traffic management, including having Indonesian personnel stationed at the Singapore Air Traffic Control Centre.

Will Changi Airport's status and future plans be affected?

On Tuesday, PM Lee was asked by Singapore reporters whether there is a concern that the FIR deal will compete with Changi's ambitions to be an air hub.

He replied that the FIR agreement is a long-term one.

And while it realigns the FIR boundaries to be generally in accordance with Indonesia's territorial boundaries, "it also makes sure that Changi is able to operate efficiently, safely, fully, provide air traffic control services in order to function as an important international airport, and to be able to grow in the long term as an international airport".

What about the other deals?

Several pacts were also inked alongside the FIR agreement, and PM Lee described the deals as "a carefully negotiated and balanced set of agreements".

"I think both sides' important interests and concerns have been met," he added.

A joint statement between the defence ministers recommits to the Defence Cooperation Agreement signed in 2007.

As part of the pact, the Singapore Armed Forces will see closer interaction with the Indonesian National Defence Forces. The SAF will also continue to conduct military training and exercises in training areas in Indonesia, as provided for under the United Nations Convention on the Law of the Sea, with full respect for Indonesia's sovereignty over its territory, including its archipelagic and territorial waters, and airspace.

Also signed was an updated extradition treaty that makes minor adjustments to the version signed in 2007. Its retrospective provisions will be extended from 15 to 18 years - meaning a fugitive can be sought up to 18 years after he has committed an offence - in line with other Indonesian laws.

To cap the deals, an exchange of letters signed by Senior Minister Teo and Mr Luhut undertakes to bring the three pacts into force simultaneously.

What's ahead?

Following the signing, Mr Teo said: "We've had 2½ years of intense and fruitful negotiations, conducted in the spirit of trust and sincerity while recognising each other's core interests and rights, and arrived at a set of balanced, mutually beneficial and durable agreements."

Added Mr Luhut: "The signing of the three documents… strengthens and enhances cooperation in the fields of law, defence and security, and reflects the constructive resolution of longstanding issues between two countries that are friends."

In Indonesia, the media and observers have hailed the FIR agreement as a historic deal for President Widodo, for regaining control of Indonesia's airspace.

Former state-owned enterprises minister Dahlan Iskan headlined his regular newspaper column Merdeka Udara (Independence of Airspace), saying: "Indonesia has attained another level of independence at the start of this year."

Meanwhile, Singapore is also assured that it will continue to provide air navigation services in the neighbourhood of Changi for at least the next 25 years, while improving relations with Indonesia.

The hope - on both sides - is that at a time of heightened global uncertainty, the positive vibes between two neighbours with a long history of cooperation in a wide range of fields will lead to a speedy ratification, and implementation, of these significant agreements.