12/05/2014 09:20 BST | Updated 12/05/2014 09:59 BST

Pfizer Reveals Legally-Binding Guarantees In AstraZeneca Takeover

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The Pfizer Inc. company logo is seen on packaging for Viagra tablets, produced by Pfizer Inc., in this arranged photograph taken in London, U.K., on Friday, May 2, 2014. AstraZeneca Plc rejected Pfizer Inc.'s sweetened takeover proposal, saying the 63.1 billion-pound ($106.5 billion) offer fails to recognize the value of the promising experimental medicines under development by the U.K.'s second-biggest drugmaker. Photographer: Chris Ratcliffe/Bloomberg via Getty Images

Pfizer has revealed the legally-binding guarantees it has offered the UK government as part of its planned takeover of UK-based rival AstraZeneca, as MPs prepare to grill the US drug giant about the deal.

In a memo to MPs, Pfizer said that it believed the takeover would create a "UK-based scientific powerhouse", pledging to establish its corporate and tax residence in England.

The American drugs giant said it would finish work on AstraZeneca's research and development hub and keep "substantial commercial manufacturing facilities at Macclesfield".

It pledges that "key scientific leadership will be located in the UK", and claims it will be "committed to meaningful participation in the UK commercial, economic and social community".

"With our commitment to foster research and development in the UK, we are matching words with deeds – and we will keep our word," Pfizer said.

AstraZeneca has twice rebuffed offers from Pfizer so far, which has tried to offer in excess of £63 billion, arguing that it has been substantially undervalued. But the US drugs giant is still keen, even hinting at a hostile takeover bid.

Pfizer boss Ian Read will be in the UK flies in to the UK for his first public defence of the proposed takeover, facing the Business, Innovation and Skills committee on Tuesday and then the science and technology committee on Wednesday.

Science committee chairman Andrew Miller previously said that Pfizer's pledge to maintain 20% of the R&D staff in the UK for five years was not sufficient, saying: "Five years is no time in drug development… we need very, very long-term commitments."

Asked if the government was taking legal advice of its own, the Prime Minister's Official Spokesman said: "We are taking a very robust approach on this."

See also: 5 Reasons Why Pfizer's AstraZeneca Takeover Plans Should Worry You

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