RN's search for an offensive role in nuclear war

While reading Eric Grove's "Vanguard to Trident" again, I found
something which may interest SMNers.

On page 44, Grove wrote:
"The ASW/fighter priority advised against putting too many scarce
resources into strike aircraft but, nevertheless, in mid-1948 studies
began of a new heavy attack aircraft with a range of perhaps two to
three thousand miles. Such a machine would give the Royal Navy the
same kind of nuclear attack capabilities as were being so assiduously
pursed by the United States Navy."

Anyone has any idea what type of aircraft it was?

Page 56
"The carrier was clearly the major surface ship. There was some debate
over the primary duty of these ships, whether they were mainly for
offensive purposes in attacking enemy naval bases or for defensive use
dealing with air and submarine threats to high-value convoys.
....
The emphasis on convoy escort was clear. As Fraser put it to the fifth
sea lord in 1948: "Planning can only proceed on something we know we
must do; escort safely our convoys." This view did not find complete
acceptance among Fraser's colleagues, especially the airmen, who
instinctively demanded a more theoretically "offensive" role."

See OA NHC Burke Papers, Personal File, #51 at
http://www.history.navy.mil/colloquia/cch8c.html

Page 98
"Not only did the Admiralty insist on keeping these two sophisticated
types (Sea Vixen and Scimitar), but it was actively pursuing once
again the concept of a nuclear-capable heavy attack aircraft. Some
kind of navalized variant of the RAF's Canberra bomber was considered,
and this led to a requirement, issued in June 1952, for a new jet
strike aircraft of much more advanced design and performance, the NA39
(Buccaneer)."

Page 105
"In return the Admiralty made the point that the main argument in
favor of the RAF's planned medium-bomber force was the influence it
might give over the general Western bomber offensive. It was as
important to have influence over the main NATO Striking Fleet's AJ-1s
or A3Ds as it was over the United States Air Force's B-47s and B-36s."