Recent buys have sparked Pfizer's shake-up

The company said the move was part of a "rationalisation" process of cutbacks following the acquisition of drugs company Pharmacia in 2003.

As a result up to 400 jobs will be cut at the group's site in Sandwich, Kent.

Meanwhile, the firm also announced plans to sell its plant in Morpeth, Northumberland, where 571 people work.

"These decisions are in no way a reflection of the hard work, loyalty and commitment of our Sandwich and Morpeth manufacturing teams," Tony Maddaluna, vice president of Pfizer global manufacturing said.

"Rather, they are a direct result of the fact-based evaluation process carried out since the Pharmacia acquisition, which has highlighted that the capacity provided by these operations is not required."

Jobs axed

The group added that the Kent jobs would be lost over the next "several years" but added that manufacturing and research and development work would continue at the plant.

A total of 500 posts are expected to remain at the site which produces cardiovascular, neurological and veterinary medicines for the UK and Ireland.

However, the company's Northumberland site - which produces medicines as well as manufacturing and packaging tablets for more than 100 global markets - was deemed surplus to requirements following its review.

A spokeswoman for the firm said that the plant would continue to operate as part of the Pfizer network until a buyer is found, adding that no redundancies were expected as a result of the decision.

Instead, the company is "optimistic" it can find a buyer for the site which will be sold as a going concern.