LONDON  - England skipper Michael Vaughan says his side's batters must regain their aggressiveness if they are to compete effectively in the Test series against New Zealand. Recent displays at the crease have been poor from England and that has badly affected team confidence, he believes. But Vaughan hopes that will now change, beginning with the Lord's Test opener, which begins on Thursday. "If you look at the last year, we have only beaten West Indies and New Zealand away," Vaughan said. "We have been under a lot of pressure and maybe that was one of the reasons we were not playing as fluently as a batting unit. "Now we have won a series away from home, we should go on and play in the more positive, fluent way we are used to. "We are all stroke-players, who get good bases and bat long periods of time when we are playing well. We do have that attacking instinct right through the order." The national selectors have opted to retain the same top six for at least the first two Tests after naming a 12-man squad for the back-to-back matches in London and at Old Trafford. Vaughan and Paul Collingwood, whose sore shoulder will be monitored during practice this week, have both suffered a lack of runs on county duty so far this summer. While Vaughan admits he is under pressure, however, he can also draw on good experience of Lord's, where he has registered five of his 17 Test hundreds. He will also recall the three-figure score he took off the West Indies attack on his return to Test cricket - after a barren trot - at Headingley a year ago. This summer, he has mustered only 135 runs in seven innings in all cricket for Yorkshire but said: "I actually feel quite good. "Obviously, I haven't got the big score. I would have loved to have got a big hundred for Yorkshire but I feel I have done the hard work by getting in at Headingley - that is usually the tricky part - on four occasions. "I have got out on those four occasions but I feel I have picked up a bit of rhythm in somewhat tricky conditions."