LONDON (Reuters) - British Prime Minister Theresa May is concerned by a newspaper report describing a culture of sexual harassment among lawmakers and their staff working in parliament, her spokeswoman said on Friday. The report in the Sun newspaper follows dozens of allegations against Hollywood producer Harvey Weinstein which have prompted hundreds of thousands of women around the world to share their own experiences. The Sun said on Friday that female staff working in London s Westminster political district had created a WhatsApp instant messaging group to discuss their experiences of harassment and warn others about potential perpetrators. It did not name anyone in connection with allegations but cited unnamed members of the group when describing its contents and purpose.    The reports are very concerning, but I can t pre-empt allegations or investigations that haven t come to light yet,  May s spokeswoman said when asked about the Sun story.  The prime minister was very clear when we responded to the reports about Harvey Weinstein in the last few weeks that any unwanted sexual behavior is completely unacceptable, and that is true in any walk of life including politics.  Separately, a group of women members of Britain s opposition Labour Party have set up a website calling on fellow members who have experienced sexual harassment within party ranks to tell their stories anonymously to try and improve Labour s culture.  Any allegations that may come to light would be taken extremely seriously and we would advise people to contact the police if there is such an allegation,  May s spokeswoman said. 