Read, who had previously made promises to protect UK jobs and research facilities in a written letter to lawmakers, said that efficiencies after any takeover would have to be achieved by eliminating some jobs. He didn’t commit to how many or where those job cuts would take place but added that the company stands by its commitment to locate 20% of its research and development workforce in Britain.

“We’ll be efficient by some reduction in jobs. What I cannot tell you is how much or how many or where,” said Read. “We’ll look at this as our global combined footprint and then we’ll make decisions.”

MORE: Pfizer CEO on AstraZeneca management: They need convincing

In order to make the $106 billion offer worthwhile, Pfizer would need to find about $3 billion worth of savings, Seamus Fernandez, an analyst with Leerink Partners, told Fortune. The savings needed would only increase if Pfizer comes back with an increased bid for the UK drug maker, which Read suggested is possible if AstraZeneca engaged in talks.

CNBC cited people with knowledge of the matter who said Pfizer (PFE) would likely wait until after its presentation to UK lawmakers before making any new move. Read had appealed directly to AstraZeneca shareholders earlier on Tuesday with a presentation that detailed the merits of the bid, and he has not yet ruled out a hostile bid, telling parliament that he had “options” for his next step.

If the deal goes forward, it would be the largest takeover of a UK company.

AstraZeneca (AZN) reacted to Pfizer’s shareholder appeal, saying that the board felt Pfizer is “making an opportunistic attempt to acquire a transformed AstraZeneca, without reflecting the value of its existing pipeline.”

The UK drug maker’s CEO, Pascal Soriot, also presented his case before the parliamentary committee on Tuesday. Soriot said “ultimately the share holders will have to decide” whether to go through with a deal, though it is “logical” to assume there will be redundancies in a merger this size.