(Reuters) - Countrywide's (>> Countrywide PLC) Chief Executive, Alison Platt, stepped down on Wednesday, a week after the British real estate agent said a loss of market share to its competitors would hit its annual profit.

Platt, who took personal responsibility for reviving the company's main sales and lettings business in August, resigned as a result of the company's current trading situation, Countrywide's newly appointed Executive Chairman Peter Long told Reuters.

"We have lost our way in sales and lettings ... she (Platt) did the honourable thing and decided to step aside," Long said.

Platt's departure comes after Britain's biggest lettings and estate firm, warned on its full-year profit and posted disappointing fourth-quarter results that sent its shares down about 20 percent.

The property services industry has suffered as a result of a drop in demand stemming from higher property taxes and the country's vote to leave the European Union.

The organisational changes made by Countrywide, along with the cooling property market, led to it losing market share to other traditional competitors, Long said.

"There has been a lot of changes in the organisation and I think that caused disruption and a negative impact in terms of our ability to sell homes." he added.

Platt took the helm in 2014 and took on more responsibilities in August as the company brought in a new organisational structure. The company said in a statement that she would also resign from the board and did not name a replacement for her.

Paul Creffield, previously managing director of the company's commercial development division, has been appointed as group operations director with immediate effect, Countrywide said.

Creffield's responsibilities would now also include the sales and lettings division, the company said.

The company also named Long, currently a non-executive chairman on the board, to become the executive chairman on Wednesday.

"Within our core Sales and Lettings area ... a key priority will be to implement changes that will enable this area to start delivering once again," Long said in a statement.

The company warned in November the market for housing transactions was challenging. At the time, Countrywide forecast results for the year ended December 31, 2017 at the lower end of market expectations.

This has forced property dealers, including Countrywide, to invest in digital expansion, close branches and slash headcount to stave off the growing threat from online agencies like Purplebricks (>> Purplebricks Group PLC) that lure customers by charging lower fees.

Countrywide's shares rose 2 percent to 102 pence at 1039 GMT.

(Reporting by Noor Zainab Hussain and Radhika Rukmangadhan in Bengaluru; Editing by Saumyadeb Chakrabarty and Elaine Hardcastle)

By Radhika Rukmangadhan and Noor Zainab Hussain

Stocks treated in this article : Countrywide PLC, Purplebricks Group PLC