STOCKHOLM, March 27 (Reuters) - H&M, the world's second-biggest listed fashion retailer, postponed the start of some Spring/Summer campaigns to adjust to shipping delays caused by the Red Sea crisis, CEO Daniel Erver said on Wednesday.

"We have made some short-term adaptation on the starting date and the launch date of campaigns," Erver told Reuters in an interview, adding the impact on what is available to customers was minor.

He said the extent of the delay would vary from country to country, but could be around two weeks in some markets.

Shipping firms have avoided the Suez Canal as militant attacks have led container vessels to be re-routed around the southern tip of Africa, adding to freight costs and delaying the arrival of clothes and shoes in Europe from factories in Asia.

H&M said in connection with its first quarter report on Wednesday that it was monitoring developments in the Red Sea and has acted to minimise any impact on the company's product availability, freight costs and stock levels.

Erver told Reuters the retailer has taken steps to limit disruption, such as asking suppliers to ship products earlier than usual, and accelerating plans to shift production closer to customers. (Reporting by Marie Mannes in Stockholm and Helen Reid in London, editing by Anna Ringstrom, Louise Rasmussen and Barbara Lewis)