Chancellor of the Exchequer George Osborne has defended the Government's interventions into the potential takeover of AstraZeneca.

Speaking at the handover of AstraZeneca's former R&D site to Alderley Park from AstraZeneca to Manchester Science Parks, he said that "our over-riding national interest is securing good jobs in science" and "we will support whatever arrangement best delivers that for Britain".

The government has been criticised by some Labour Party politicians for being seen as supportive of the Pfizer, a claim Mr Osborne refutes. However, he added that it is a key part of his job to engage with the management of AstraZeneca and Pfizer to secure the UK's economic interests.

The chancellor (pictured) had a dig at Labour leader Ed Miliband who had reportedly turned down a meeting with Pfizer chief executive Ian Read (though they will speak this week), saying it is "a huge error of judgement not to engage with AstraZeneca and Pfizer". He claimed that "if you are not in the room or at the end of the phone call", it is hard to put "British science and jobs first".

Later Mr Osborne told the BBC he would be asking Pfizer executives for "real promises that we can hold them to", and is prepared to be "very hard-nosed" with big firms "about what we want to deliver in terms of good British science and good British jobs". However, shadow business secretary Chuka Umunna reiterated his concerns about a deal saying that "the assurances Pfizer has given are not worth the paper they are written on, given that Pfizer has since refused to rule out breaking up AstraZeneca and selling off parts of it in the future".

Pfizer's Mr Read and his AstraZeneca counterpart Pascal Soriot will appear before the Commons Business Committee on Tuesday and the Science and Technology Committee the day after.