Royalist was withdrawn from the East Indies after the conclusion of hostilities, and returned home to be mothballed and dehumidified in 1946.
The reconstruction of Royalist from deep preservation with new superstructure and advanced interim fire control fitted involved major work but was intended to extend the cruiser's life for only 6 years.
Diadem was better preserved and was offered to the RNZN as an alternative in 1955.
In an 18-month refit, Diadem was updated and renamed Babur for Pakistan, 
As with the transfer of Royalist to the RNZN, the transfer of Diadem to Pakistan was controversial over the high cost of the refit.
 Royalist and Diadem were complex warships even as built in 1944.
After refit and rewiring in 1956 they could never really be turned off for more updating and had to be kept running with 200 men aboard even for short periods in reserve and refit; difficult for small navies such as the RNZN.
In March 1953 Royalist had started a three year major reconstruction   The "facelift' (new superstructure and electronics, but old engines) of Royalist was announced to start a large Dido/Bellona update programme.
However the new PM, Churchill, favoured the RAF and the 1952 Navy Estimates was reduced.

The RAF had priority and the Royal Navy view that development should centre on frigates and large carriers was not liked by the old PM and the cruiser reconstruction programme was suspended for three years;  also delayed by the immediate and changing priorities of the Korean War and the great difficulty and expense of developing compact steam propulsion with adequate range and speed and good close in defence for the destroyers and frigates.
A radical defence review in June 1953 saw heavy naval cuts but Royalists modernisation continued under a revised defence White Paper in February 1954 which restored the RN programme and plans to complete Hermes and the Tigers, but rejected starting further Dido/ Bellona conversions; they lacked the 'dual war and peace, cold war capabilities' required for the RN.
The postwar RN programme envisaged that Soviet bombers would be improved Boeing B-29 Superfortress (Tupolev Tu-4) or Lincolns flying at 320 mph at 4.4 miles height, however on May Day 1954, it was clear 5.25 guns would be marginal against the new Soviet Tupolev Tu-16 "Badger" and Myasishchev M-4 "Bison" bombers flying 7 miles high at 600 mph (520 kn); it took 30 seconds for 5.25-inch shells to reach that height.
A frigate with just one Mk 6 4.5-inch turret could not destroy jets 5.5 miles high.
 But Royalist was then suspended and reviewed in the 1955 Defence White Paper which  decided on a scaled down cruiser programme of extended refit for colonial rather than NATO service.

The NZ Prime Minister Sid Holland decided to accept to purchase a reconditioned Royalist for £4 million in  March 1955 after a seven week visit to the US and UK where he met Richard Nixon, John Foster Dulles and Churchill who stressed the new strategic reality of hydrogen bombs.
Holland told the NZ Parliament than he was mainly influenced by the advice of the British Minister of Defence Harold Macmillan, who stressed the need to refocus NZ defence on the Pacific and shorter lines of communication to the SE Asian rather than Middle East theatre.
British First Sea Lord and Admiralty Minister stressed the immediate availability of 'Royalist' and that while an order of two or three anti-submarine frigates would probably proceed, the type was untested and unproven, and the RN did not view either the anti-submarine or anti-aircraft frigates being produced in 1955 as suitable for New Zealand and it was desirable to wait for new types of  frigates suitable for NZ conditions with more gun power and anti-submarine capability: modified Whitby-class frigates or redesigned Type 41 frigates with 3/70 or 4/62  gun turrets effective against missiles and jets
The cost of Royalist's reconstruction reached £4.5 million. (
the cost of two new 2500-ton frigates).
A minority of RNZN opinion, including Cpt Phipps, saw it as a policy reversal stopping the RNZN maintaining a
Royalist was withdrawn from the East Indies after the conclusion of hostilities, and returned home to be mothballed and dehumidified in 1946. The reconstruction of Royalist from deep preservation with new superstructure and advanced interim fire control fitted involved major work but was intended to extend the cruiser's life for only 6 years. Diadem was better preserved and was offered to the RNZN as an alternative in 1955. In an 18-month refit, Diadem was updated and renamed Babur for Pakistan, 
As with the transfer of Royalist to the RNZN, the transfer of Diadem to Pakistan was controversial over the high cost of the refit.  Royalist and Diadem were complex warships even as built in 1944. After refit and rewiring in 1956 they could never really be turned off for more updating and had to be kept running with 200 men aboard even for short periods in reserve and refit; difficult for small navies such as the RNZN. In March 1953 Royalist had started a three year major reconstruction   The "facelift' (new superstructure and electronics, but old engines) of Royalist was announced to start a large Dido/Bellona update programme. However the new PM, Churchill, favoured the RAF and the 1952 Navy Estimates was reduced. 
The RAF had priority and the Royal Navy view that development should centre on frigates and large carriers was not liked by the old PM and the cruiser reconstruction programme was suspended for three years;  also delayed by the immediate and changing priorities of the Korean War and the great difficulty and expense of developing compact steam propulsion with adequate range and speed and good close in defence for the destroyers and frigates. A radical defence review in June 1953 saw heavy naval cuts but Royalists modernisation continued under a revised defence White Paper in February 1954 which restored the RN programme and plans to complete Hermes and the Tigers, but rejected starting further Dido/ Bellona conversions; they lacked the 'dual war and peace, cold war capabilities' required for the RN. The postwar RN programme envisaged that Soviet bombers would be improved Boeing B-29 Superfortress (Tupolev Tu-4) or Lincolns flying at 320 mph at 4.4 miles height, however on May Day 1954, it was clear 5.25 guns would be marginal against the new Soviet Tupolev Tu-16 "Badger" and Myasishchev M-4 "Bison" bombers flying 7 miles high at 600 mph (520 kn); it took 30 seconds for 5.25-inch shells to reach that height. A frigate with just one Mk 6 4.5-inch turret could not destroy jets 5.5 miles high.  But Royalist was then suspended and reviewed in the 1955 Defence White Paper which  decided on a scaled down cruiser programme of extended refit for colonial rather than NATO service.
The NZ Prime Minister Sid Holland decided to accept to purchase a reconditioned Royalist for £4 million in  March 1955 after a seven week visit to the US and UK where he met Richard Nixon, John Foster Dulles and Churchill who stressed the new strategic reality of hydrogen bombs. Holland told the NZ Parliament than he was mainly influenced by the advice of the British Minister of Defence Harold Macmillan, who stressed the need to refocus NZ defence on the Pacific and shorter lines of communication to the SE Asian rather than Middle East theatre. British First Sea Lord and Admiralty Minister stressed the immediate availability of 'Royalist' and that while an order of two or three anti-submarine frigates would probably proceed, the type was untested and unproven, and the RN did not view either the anti-submarine or anti-aircraft frigates being produced in 1955 as suitable for New Zealand and it was desirable to wait for new types of  frigates suitable for NZ conditions with more gun power and anti-submarine capability: modified Whitby-class frigates or redesigned Type 41 frigates with 3/70 or 4/62  gun turrets effective against missiles and jets
The cost of Royalist's reconstruction reached £4.5 million. (the cost of two new 2500-ton frigates). A minority of RNZN opinion, including Cpt Phipps, saw it as a policy reversal stopping the RNZN maintaining a
HMS Royalist (89)