I’m in Tokyo with the PM and a business delegation. David Cameron says he’s here to help to re-balance the UK economy, to fill the gap left by the shrunken financial sector with more exports. Mr Cameron said he was unashamed and “up front” about packing a plane with businessmen including several big defence contractors (BAE systems, AgustaWestland, Thales and MBDA amongst them) saying it’s part of what being a PM is about.

The Japanese have only just relaxed their ban on military technology deals with anyone but the Americans. The Department for Business, Innovation and Skills thinks there are serious business opportunities for the UK. They could end up a lot more significant than the Nissan inward investment trumpeted overnight.

As could nuclear industry deals – there’s quite a nuclear presence on the trip too and though these businessmen are emphasising the potential for partnerships in growth, a senior nuclear industry source made it clear that there were possible clean-up contracts to be sought if Japan decides to decommission its 54 nuclear power stations, nearly all of which are currently “off-line.”

Before coming on the trip, the PM has been reflecting on what his big message for the voters is after a punishing two weeks which saw his personal poll ratings plummet. He’s emphasising that his is a long term approach taking decisions in the national interest. Asked about whether he acknowledged he’d taken a hit in popularity after the abolition of the 50p rate the PM said he was more interested in competitiveness not a popularity contest.

You get the impression over the past couple of weeks that the PM blames the Lib Dems for a significant part of his woes – leaking Budget details so the focus fell on the “granny tax” on the day as the only big “new” measure. And on the plane you detected a hefty swipe at Nick Clegg over what No. 10 seems to see as a pretty blatant, grandstanding, grassroots-pleasing u-turn on security measures.

The PM said the Deputy PM (along with Chris Huhne and Ken Clarke, amongst others) had much earlier signed up to measures proposing additional surveillance and secret court hearings in cabinet committee (chaired by Nick Clegg) and at the National Security Council and sounded like a man who had every intention of making sure the measures agreed at those meetings come into law.

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