Opera House to light up in French colours

The Sydney Opera House will be lit up in the colours of the French flag as a tribute to the victims of the Paris terror attacks.

Two church services will also be held in Sydney to remember the scores of victims killed in the unprecedented attacks.

St Andrews Cathedral will hold a prayer vigil at 3pm on Sunday, while a memorial service will be held at St Marys Cathedral at 6.30pm on Monday, NSW Premier Mike Baird has announced.

It's expected the Opera House will be illuminated in red, white and blue about 9pm on Saturday.

Mr Baird said he had also asked for a French flag to fly over the Harbour Bridge.

"There isn't one in the country big enough. If we cant find one, we'll make one," he tweeted on Saturday.

Brisbane Mayor Graham Quirk said the river city's Story Bridge would also be lit up in red, white and blue on Saturday night in a show of solidarity.