"When we looked at AZ, we liked their science," Reid said in a series of online videos. "We liked where their science is being done, which is in the U.K., and we know we have good science in the U.K. in Cambridge, Oxford, London and other universities.
Read was responding to increasing concern that jobs would be lost if Pfizer were to acquire AstraZeneca, especially as the U.S. company said in 2011 that it would cut 1,700 jobs when it closed a facility in Sandwich in southern England.
Pfizer has promised to protect R&D jobs in the U.K. but said it could adjust its pledges if circumstances "significantly" alter, prompting calls for stronger commitments, such as from British finance chief George Osborne.
The possible merger has also sparked concern in the U.S. and Sweden. Members of Congress from Maryland and Massachusetts, where AstraZeneca and Pfizer have facilities, are particularly worried about possible job losses.