SINGAPORE - Singapore should repeal its ban on foreign companies sponsoring the annual Pink Dot gay-pride event, Human Rights Watch said, complaining that it infringed freedom of expression in the city state.Singapore announced this month that foreign firms would no longer be allowed to sponsor or participate in the rally, after this year's event drew record numbers of people and a record nine corporate sponsors, including Twitter, Google and Facebook.The announcement came after this year's event on June 4."The ministry's June 7 statement sends a discriminatory message to Pink Dot's corporate sponsors that their support for the festival is contrary to government policy," Human Rights Watch said in a letter to Home Minister K. Shanmugam."This infringes on rights to freedom of expression, which the Universal Declaration of Human Rights guarantees to 'everyone', and pressures corporations to act in contravention of their responsibilities under the United Nations Guiding Principles on Business and Human Rights."The ministry said it had no immediate comment.