Washington, Jan 25 (IANS): US President Donald Trump vied for the votes of evangelical Christians and other conservatives with an unprecedented appearance at the country's largest annual anti-abortion gathering.

Trump on Friday became the first sitting US President to deliver an in-person speech to the "March for Life", a rally held every year since 1974 in Washington D.C. to protest the legalization of abortion through the Supreme Court's landmark "Roe v. Wade" decision in January 1973, reports Efe news.

"Unborn children have never had a stronger defender in the White House," Trump told a cheering throng of supporters on the National Mall, a rare occurrence in an overwhelmingly Democratic city where his impeachment trial is taking place in the Senate.

"(The Democrats) are coming after me because I'm fighting for you. And we're fighting for those who have no voice," Trump said.

The President, meanwhile, did not hesitate to urge the rally attendees to support his re-election bid in November, directing his message in particular to women in the crowd.

"Today, millions of extraordinary women across America are using the power of their votes to fight for the first right in the Declaration of Independence - the Right to Life," Trump said.

Trump, who just two decades ago had said he was "very pro-choice", changed his position a few years before running for President. (No Republican presidential nominee has ever declared himself to be pro-choice).

"From the first day in office I've taken historic action to support America's families and to protect the unborn," Trump said, adding that he has appointed a record number of conservative judges who can deliver courtroom victories for anti-abortion activists.

Those attending the "March for Life," including many teenagers who arrived on buses chartered by their local churches in different parts of the country, later marched to the Supreme Court to call for Roe v. Wade to be overturned.