Thousands of people marched to the Martin Luther King Jr Memorial in Washington on Saturday, commemorating the 50th anniversary of his 1963 “I Have a Dream” speech and pledging that his vision also included equality for gay and lesbian people.

US Attorney General Eric Holder was one of the many speakers at the rally to honour the occasion.

In his remarks, Mr Holder said the struggle for civil rights has widened to include many other groups, including gays and lesbians, women, Latinos, poor people, and the disabled.

Addressing the gathering crowd in front of the Lincoln Memorial, he said: “As we gather today, 50 years later, their march – now our march – goes on.

“And our focus has broadened to include the cause of women, of Latinos, of Asian Americans, of lesbians, of gays, of people with disabilities, and of countless others across this country who still yearn for equality, opportunity, and fair treatment.”

The rally was named the National Action to Realize the Dream March. It is one of the multiple events commemorating the 1963 march.

Last week a number of gay rights organisations, including Get Equal, Human Rights Campaign, National Black Justice Coalition, National Gay and Lesbian Task Force and Pride at Work, AFL-CIO, signed a letter in support of the ceremony.

In an open letter, the groups wrote: “As national, state and local LGBTQ organizations, we know that while there have been many advancements over the last four decades since Stonewall and the five decades since the 1963 March, there is still much more work to be done.

“We are proud to commemorate the 1963 March and, once again, come together and collectively take action to ‘Realize the Dream.’”

“This is not the time for nostalgic commemoration,” said Martin Luther King III, the oldest son of the late civil rights leader. “Nor is this the time for self-congratulatory celebration. The task is not done. The journey is not complete. We can and we must do more.”

Earlier this month, a the request of Washington DC Mayor Vincent Gray, an “ex-gay” gospel singer withdrew from his performance at another Martin Luther King memorial.

Donnie McClurkin, was previously announced to have join President Obama to honour the 50th anniversary of Martin Luther King’s “I have a dream” speech.

Mr McClurkin is notorious for his statements claiming religion rescued him from homosexuality. In 2007, the singer came under similar controversy when he was scheduled as Barack Obama’s promotional artist in his bid for presidency.