One of the world's largest cruise companies, Royal Caribbean International, wants a new passenger terminal at Botany Bay capable of handling the newest generation of mega cruise ships carrying 3000 to 6000 or more passengers.

The company's commercial manager, Adam Armstrong, said provisioning ships at the Overseas Passenger Terminal near Circular Quay was difficult and crowded

And only four of the company's 44 cruise ships could fit under the Harbour Bridge to travel to White Bay, where the new cruise terminal will be located.

''A solution east of the bridge is urgently required,'' he said.

Royal Caribbean approached the Minister for Ports, Duncan Gay, with its proposal a few months ago, a spokesman for the minister said.

Mr Gay visited the Port Botany site with company executives, but he said any decision about whether Port Botany was used as a cruise terminal was ''really a decision for the stevedore lessees''.

Port Botany includes two container terminals with six container vessel berths, operated by Patrick Ports and Stevedoring and DP World. A third company, Hutchison Port Holdings - one of the world's largest port operators - is building a new container terminal as part of the $1 billion Port Botany Expansion project.

Hutchison's spokesman, Pat Wilson, said the company was well advanced in developing its new container terminal which would have a high level of automation.

''Passenger and container terminals, particularly those with a high level of automation, don't mix,'' he said.

Would arriving in Port Botany have the same wow factor as arriving in Circular Quay?

Mr Armstrong conceded that it would not be as glamorous but it would be far more efficient to land passengers at Port Botany than Circular Quay.

Botany had ''excellent road, rail and airport links which would avoid navigating the busy streets of Sydney's CBD''.

He said it would also make it easier to load fuel and stores on trucks, which was problematic in the CBD.

The company's proposal did not get the support of Ann Sherry, the chief executive of Carnival Cruises.

''Spectacular cruise ship arrivals and departures from Sydney Harbour are integral to the cruise holiday experience and have contributed to the remarkable growth of cruising in Australia in recent years and its growing economic contribution,'' she said.

The NSW government believes the booming cruise industry, which has benefited from cut-price berthing of only $250 an hour in the past five years, should fund any additional infrastructure.