The planned changes to key bus services in Bukit Panjang - including the removal of two linking the area directly to the city - have touched a raw nerve among residents.

From Aug 16, bus services 700 and 700A, which link Bukit Panjang to areas such as Orchard Road, Bras Basah and Shenton Way, will stop operating, while service 171, which links Yishun to Marina Centre and passes Bukit Panjang, will be shortened. Service 972, which links Bukit Panjang to Orchard Road, will be rerouted to Newton MRT station.

The changes to these services, which ply along the MRT Downtown Line (DTL) - which runs from Bukit Panjang to Expo in the east - were announced by operator SMRT on Monday afternoon.

Three petitions have since been put up to halt the planned changes. They garnered more than 1,000 names within the first 24 hours.

MPs have weighed in on the issue, while SMRT's post has drawn more than 400 comments and was shared over 900 times on Facebook as of yesterday evening.

Bukit Panjang MP Liang Eng Hwa said he was "very disappointed" that the Land Transport Authority (LTA) has decided to go ahead with the changes, which he described as drastic. "We are aware that ridership for service 700 has fallen sharply, and that is why we are prepared to work on a compromise solution," he said.

"I hope LTA can be open-minded and not see discontinuing services as the only way out. For many years, Bukit Panjang has faced problems with public transport, and it took the town's MPs a great deal of effort over the last decade to improve services to its current level."

Mr Edward Chia, a first-term MP from neighbouring Holland-Bukit Timah GRC, said the changes will have deep impact on the daily lives of residents. "Hence, I hope that LTA will reconsider, delay these changes and review its plans."

The changes to the routes, which serve residents from both constituencies, will mean some commuters losing direct connections to areas previously served by the buses. Some will have to make transfers, resulting in longer commutes.

Replying to queries from The Straits Times, the LTA, which plans all bus routes, said the latest change "has been a difficult decision".

It said that since Phase 2 of the DTL opened in December 2015, ridership for bus services plying along the line has fallen.

Ridership has fallen by more than 30 per cent for service 171, and by more than 50 per cent for service 700. The LTA has therefore been subsidising the services - to the tune of $5 million a year for service 700.

It said the route of service 972 will be changed to "maintain the connectivity" after service 700 is removed.

The authority said it is aware that the changes will lead to longer travel time for some residents, but it "needs to balance the needs of different groups of commuters".

"If this is the only transport option in the area, we can justify the public spending. But given that DTL is available as an alternative, we need to exercise prudence in the use of public funds," it added.

Rationalisation of bus services plying along MRT lines has been a way for the LTA to avoid duplication of resources.

Scores of routes were withdrawn or amended soon after the first MRT line started operating in 1987, and several services were halted when the North East Line started operating in 2003. After a public outcry, some bus routes were reintroduced to the area.

Then Transport Minister Raymond Lim allowed some bus services to run along MRT lines during his tenure from 2006 to 2011.

His successor, Mr Lui Tuck Yew, continued to do so when the Bus Service Enhancement Programme (BSEP) - funded by more than $1 billion in tax monies - was rolled out in 2012. Mr Lui also introduced city-direct bus services which competed directly with the MRT.

But in 2017, Mr Lui's successor Khaw Boon Wan, who has since retired, revisited the topic of bus rationalisation. Mr Khaw said that "while co-payment by taxpayers is appropriate, we have to make sure that the burden on taxpayers does not become excessive".

"We hope commuters bear in mind the need for prudence, the need for bus service rationalisation and the need for fare adjustments," he said.

Bukit Panjang resident Elliot Lin said Bukit Panjang and neighbouring Choa Chu Kang have long had poor public transport connectivity.

Relief came when the BSEP was rolled out. Bus service 972 was one such addition from the programme.

"Now we are back to square one," said Mr Lin, 35, a real estate agent. "I understand there is sometimes a need to rationalise bus services, but for this area, there are only two services going to town."

He said his wife's journey to her workplace at Singapore General Hospital will take at least 20 more minutes with the changes.

The impact of the changes is not insignificant, he added. "There are 35,000 residents living here."