* ASOS posts improved Q3 GMV, new customer growth up 9%

in March

* ASOS seeks $9.44 million in US tariff refunds

* CEO says ASOS has not yet changed prices due to Iran

war

(Adds shares in paragraph 2, analyst comment in 4, CEO comment

in 6, details throughout)

By Yamini Kalia

April 23 (Reuters) - ASOS said on Thursday it

had improved its performance in the third quarter, adding that

the British online retailer is seeking refunds for 7 million

pounds ($9.44 million) in U.S. tariffs paid during the first

half of the year.

Shares in ASOS rose by as much as 10.7% to 249 pence after

volatile early moves as investors digested the performance

report, which followed last month's release of its topline

numbers for the 26 weeks to March 1.

ASOS said its gross merchandise value (GMV) growth showed

sequential improvement in the third quarter and new customer

growth was up 9% in March, the first month of growth since

September 2021, as it fends off competition from cheaper rivals

and prioritises margins.

"The new customer growth is a good lead indicator for top

line, so that gives us confidence it the long term turnaround,"

said Shore Capital analyst Katie Cousins.

GLOOMY RETAIL ENVIRONMENT

Retailers globally are facing falls in customer spending,

higher energy costs and supply-chain snags resulting from the

Iran war, with some pushing up price tags in response.

"We price according to the market ... if the market is not

changing the prices, we are not changing the prices," CEO José

Antonio Ramos Calamonte told reporters when asked whether ASOS

had taken any pricing actions in response to the conflict.

British clothing retailer Next said last month it

may need to raise prices in June if the conflict persists.

Thousands of companies around the world are filing lawsuits

challenging U.S. President Donald Trump's sweeping tariffs and

seeking refunds on duties paid, after the levies were deemed

illegal by the U.S. Supreme Court in February.

Online retailers are particularly vulnerable to duty costs

on imported goods.

($1 = 0.7413 pounds)