In a statement on its website last Tuesday, the ministry said that the Singaporean government generally rejects foreign entities interfering in domestic issues.
"These are political, social or moral choices for Singaporeans to decide for ourselves," it said.
The city-state's ministry of home affairs has said it will "take steps to make it clear that foreign entities should not fund, support or influence such events".
The move by Singapore's government comes after conservative activists have accused multinationals of interfering in Singapore's politics and have called on them to withdraw sponsorship.
Pink Dot lists tech companies Facebook, Apple and Google, as well as financial giants Barclays, J.P. Morgan and Goldman Sachs, among its corporate sponsors.
The statement concludes: "In the context of LGBT issues, this will apply both to events that advocate the LGBT cause such as the Pink Dot, as well as events whose purpose is to oppose the LGBT cause."
Pink Dot's own statement, posted on its website Wednesday, reads:
"Pink Dot SG started off first and foremost as a platform on which values of inclusion and diversity are celebrated, and over the years this has only strengthened with the growing support of Singaporeans from all walks of life, including a significant portion of its corporate citizens.
For all the LGBT Singaporeans and their allies that this movement has striven to help give a voice to and done its part to push the envelope in helping to create greater visibility of Singapore's LGBT community, we have done all we can to ensure Pink Dot SG stays within the law.
Our Corporate Sponsors that have supported us over the years are all registered and incorporated in Singapore. We are fortunate to count among them admired household names, employers of choice for a sizeable portion of our workforce, inextricably linked with and fully a part of this beautiful fabric we call home."