IT would be pleasant to be able to report that China's agreement at the last Joint Liaison Group (JLG) meeting to allow Hong Kong to proceed with the first stage of the localisation of civil aviation legislation signalled a new sense of urgency and co-operation. The rest of the news from that meeting, however, was bad. Progress was lacking on a range of urgent business items, from defence lands to mutual legal assistance. And, as Secretary for Constitutional Affairs Michael Sze Cho-cheung again told Legislative Councillors yesterday, the impasse was all down to the ''climate''. For which read: political climate. The consequences of this stalemate are all too clear. It is becoming more and more likely - and official recognition of the matter may well be only a matter of time - that Hong Kong's new airport will not be completed before July, 1997 - not without urgent agreement from China. Beijing's similarly stubborn refusal to give the go ahead for Container Terminal 9 threatens economic growth. The slow pace of localising laws could lead to a legal vacuum in 1997. China likes to blame Britain for every hitch in the transition, with the damage to relations over political development being the latest excuse for digging in its heels. But whatever the political situation, it is hardly credible that Britain should be the culprit in holding up the airport negotiations. The Governor has every reason to wish to leave Hong Kong from an airport he helped build. Why should he encourage delays and deny himself the glory? Yet China repeatedly claims it has the interests and livelihood of Hong Kong people at heart. Its behaviour so far suggests that it is more pre-occupied with its battle with Britain. The JLG, however, is meant to be a forum for co-operation and sorting out the nitty-gritty detail of the transition. It is not the place for political confrontation. It is time Beijing paid more than lip-service to the view that Hong Kong's confidence and prosperity will not be maintained by vindictiveness or by choking its growth.