Balakrishnan’s briefing of the legislature on the row followed Singapore’s 11th-hour decision to postpone a high-level meeting between the two sides, which was to have taken place on Monday, citing provocations from Malaysia.

“I do not expect a quick or smooth resolution to all these issues,” Balakrishnan said, according to local media.

He said Malaysia’s actions “created the risk for a dangerous downward spiral of measures and countermeasures”.

“Despite these current difficulties, Singapore still hopes to work with Malaysia for better relations, and closer cooperation that benefits both sides,” he said, adding that both countries needed to “act in good faith, in compliance with international law and norms, and honour existing agreements”.

The row – on the boil since December – had appeared to simmer down last week after Balakrishnan met with his Malaysian counterpart Saifuddin Abdullah to discuss the two disputes.

The air boundary row is over Malaysia’s objections to a Singaporean plan to broadcast a new radar system over the state of Johor – a move the Malaysian government views as inconveniencing residents and restricting industrial development there.

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The sea dispute, meanwhile, stems from Malaysia’s decision in October to extend the limits of a seaport into waters the island republic had long patrolled and deemed its own.

After the unilateral declaration, Malaysian government vessels have patrolled and anchored in the disputed waters.

The two foreign ministers had agreed to concessions and a time frame for further talks on these two issues, but Balakrishnan said actions by the Chief Minister of Johor, Osman Sapian, ran contrary to this understanding.

A day after the foreign ministers’ meeting, Osman boarded one of the Malaysian vessels and posted pictures of his visit on Facebook.

Singapore’s foreign ministry slammed the visit as “provocative”, and in a retaliatory move postponed the planned bilateral meeting, in which Osman was supposed to take part.

His visit “undermined the goodwill and trust necessary for further cooperation between the two countries, especially involving Johor”, Balakrishnan told parliament. “It made it untenable to proceed with the [meeting].”

Osman had earlier told Malaysian media he had not intended to “cause trouble”, but had gone on board the vessel, the MV Pedoman, as a show of support to the “civil servants” who were manning it.

Mustafa Izzuddin, a Singaporean researcher who studies bilateral ties between the two countries, said he believed Osman had acted “unilaterally”, thus jeopardising joint efforts to find a solution to the dispute.

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“The move … was unwise, imprudent, and counterproductive to efforts being undertaken by the federal government to mend Malaysia-Singapore relations,” the ISEAS-Yusof Ishak Institute research fellow said.

Singapore-based independent pollster David Black, meanwhile, said a recent survey conducted by his firm Blackbox Research showed a majority of Singaporeans were either “very concerned” or “somewhat concerned” about the dispute – which unwinds years of relatively balmy ties between the neighbours.

“Seven in 10 worried about the economic consequences – the damage to Singapore’s maritime hub status. It’s a big business for Singapore, so need this to go away or we will suffer for it,” Black said.

He said most of the 1,000 respondents said the best solution to the saga was for “everyone to sit down and sort things out”.

Singaporean establishment voices, including retired diplomat Bilahari Kausikan, have said they believed Mahathir himself might be the source of the tensions, as he was using the Lion City as an “external bogeyman” amid rising pressure at home.

Such accusations were routinely levelled at Mahathir by Singaporean leaders during his first stint in power from 1981 to 2003.

In Malaysia, there appeared to be little such hand-wringing.

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While the dispute has dominated social media discussions in Singapore, Malaysians have appeared more focused on internal political machinations – including an upcoming by-election.

Malaysia’s Economic Affairs Minister Azmin Ali, a key Mahathir liutenant who was to have led his country’s delegation in the postponed meeting, made the trip to the Lion City despite the change of plans.

He held meetings with Balakrishnan and other Singaporean ministers on Monday, and sought to send the message that the two governments would press on with talks despite the latest setback.

“We are each other’s closest neighbour connected by deep historical ties and family bonds,” Azmin said of the two countries, which split acrimoniously in 1965. “Let’s work things out for the well-being and future of our people.”