A journalist for Iran's English-language Press TV has been arrested in the United States, the news channel said on Wednesday.

US-born Marzieh Hashemi was arrested on arrival at St Louis Lambert International Airport on Sunday, according to family and friends cited by Press TV.

“The US officials have so far refused to provide any reasons for her apprehension either to her or her family,” the broadcaster said on its website.

It added that Hashemi, a Muslim convert who changed her name from Melanie Franklin, had been visiting “her ill brother and other family members.”

Press TV claimed that all she had been offered to eat was pork, religiously forbidden for Muslims.

The broadcaster was due to hold a press conference on her case later on Wednesday.