Councillors have welcomed a long-awaited investment in Wycombe Hospital, but say the town is still being let down by the lack of an Accident and Emergency department.

An initial £20 million investment from NHS England will fund a new six-storey building and Endoscopy Unit at Wycombe Hospital, the first phase of redevelopment.

But councillors say the plans still fall short of what residents have campaigned for since A&E services were removed 20 years ago.

Cllr Darren Hayday, who has campaigned for A&E to return since 2009, said his view hasn’t changed after years of effort.

“We are in a dead spot in Wycombe where Wexham, Stoke Mandeville or the John Radcliffe is all a very long commute away,” he said. “We in Wycombe still need an A&E department.”

Cllr Khalil Ahmed said he welcomed investment in the hospital but warned that the absence of an A&E, continued to leave what he called “a significant and unacceptable gap in emergency care” for a growing population.

“Our town has expanded significantly,” he said. “These upgrades cannot be seen as a substitute for a fully functioning A&E department. We need services that meet the urgent and immediate needs of our residents, right here in Wycombe.”

Cllr Lesley Clarke OBE said it was disappointing that town would not be getting an A&E department but that she was pleased to see the investment in the hospital.

Cllr Clarke said: “Wycombe Hospital … is a centre of excellence for both Heart and Stroke… both very important in this day and age.”

She also voiced concern over the loss of parking and said she hoped alternative spaces and improved bus links would be provided.

Cllr Julia Wassell, who campaigned against the A&E closure, said changes in national health policy mean its return is now unlikely.

“I was one of the campaigners in 2005 and a 40,000-signature petition was submitted,” Cllr Wassell said.

“[But] given that dozens of other A&E departments have now closed across the country I doubt it will return though I know that it is greatly missed and the distance makes life difficult.”

She also pointed to the vacant site next to Wycombe Hospital, the former Staples site, and said she has challenged the Trust to consider purchasing it for future use.

Cllrs Hazel Arthur-Hewitt, Chris Chilton and Majid Hussain welcomed the funding, saying the redevelopment would secure Wycombe’s existing hospital services and praised MP Emma Reynolds for ensuring the town was not left behind.

A Buckinghamshire Healthcare NHS Trust spokesperson said Wycombe already provides specialist emergency care for heart and stroke patients, with an ICU and urgent treatment centre on site.