A “fourth and final” offer from Pfizer has been rejected by AstraZeneca.

The UK pharmaceutical company claims the £69bn offer is inadequate as the US drugs giant has been trying to takeover the company.

AstraZeneca shares plunged by as much as 15% when the offer was declined.

Critics say a deal could put UK research and development jobs under threat.

Pfizer still employs 700 people at Discovery Park in Sandwich since its close in 2011, when Pfizer quit its base at Sandwich leaving hundreds of people unemployed.

The bid comes after a week of talks in parliament over the merger, and MP Laura Sandys has been calling for the security of jobs in Sandwich to remain a high priority.

Many feel that Pfizer’s pull-out of Sandwich was a massive blow not just for the town but for east Kent as a whole and the remaining jobs must therefore be saved.

Cllr John Bragg, a former Pfizer employee and Sandwich town councillor said: “Pfizer leaving was a big blow for east Kent but not for Sandwich, it was a blow to our pride and many people didn’t like the idea of an empty warehouse, that was a blow.

“Many of them that were here are no longer in Sandwich, they went looking for a job somewhere else and that did change our local economy but most people never even lived in Sandwich.”

Cllr Bragg explained that he believes the Sandwich site will remain at Discovery Park whether a merger takes place or not.

He said: “They will keep them there as they have special equipment they’re using which will keep them there until the project is finished.

“I can’t see them [Pfizer] coming back here at all but if they did I don’t think people would believe them.”

He believes that the incident has damaged Pfizer’s reputation in east Kent.

AstraZeneca outlined four key points underlying its rejection of the deal, starting with planned cost-cutting which would “imply a meaningful reduction in research and development potential and capabilities.”

In addition, Astra said integration would risk “significant disruption” to the delivery of its new drugs - echoing chief executive Pascal Soriot’s claim before MPs that life-saving medicines could be delayed by the distraction caused.

The UK firm pointed as well to Pfizer’s past record, saying its previous large-scale takeovers had “highlighted the challenges around the negative impact of integration on research and development productivity and output.”

Pfizer has promised not to make a hostile takeover which would appeal directly to shareholders rather than going through the board members.