An independence referendum on the other side of the globe could reignite debate about Australia's national flag.

The people of Scotland will go to the polls in September next year to determine whether the country should achieve independence from the United Kingdom.

The blue in the Union Jack represents the Scottish national flag (the Saltire, or flag of St Andrew). Credit:Jeff J Mitchell

As the blue in the Union Jack represents the Scottish national flag (the Saltire, or flag of St Andrew), there has already been debate in Britain about whether the flag would need to be amended should the Scots choose to go it alone.

The make-up of the Australian national flag is defined in the Flags Act of 1953, which includes ''the Union Jack occupying the upper quarter next the staff''.