The founder and chief executive of online estate agency Purplebricks has quit the business.

The announcement by Michael Bruce coincides with the Solihull-based company saying it will exit the Australian market and place its US operations under review.

Mr Bruce will step down with immediate effect, just months after its shares tumbled when it cut annual revenue guidance and announced the departure of the bosses of its UK and US units.

He will be replaced by Vic Darvey, previously the company's chief operating officer.

Chairman Paul Pindar thanked Mr Bruce for his contribution to the creation and development of Purplebricks but added that the firm had got things drastically wrong over the past year.

He said: "We are very conscious that the group's performance has been disappointing over the last 12 months and we sincerely apologise to shareholders for that.

"With hindsight, our rate of geographic expansion was too rapid and as a result the quality of execution has suffered.

"We have also made sub-optimal decisions in allocating capital. We will learn from these errors and will not make them again."

Purplebricks bemoaned "increasingly challenging" conditions in Australia and confessed to "execution errors", adding that returns from the nation are "not sufficient to justify continued investment".

It will now commence an "orderly run down" with immediate effect, pending closure.

In the US, Purplebricks has put its operations under review.

The firm said: "Whilst good progress has been made in launching our brand across the US, the board has materially cut investment in marketing and other overheads to reduce expenditure to sustainable levels and begun a strategic review."

In February, Purplebricks warned over headwinds in the Australian housing market when it admitted that it did not expect to meet revenue forecasts for the year.

In the US, the company cautioned there had been a "slower-than-expected response" to its marketing initiative and it also does not expect US revenue to meet expectations.

To compound matters, last month analysts downgraded the online estate agent and said it would have to raise fresh cash.