US embassies in Europe have invited an instrumental figure in the movement to legalize same-sex marriage to visit three countries where it is not yet legal.

Evan Wolfson, founder of marriage equality campaign group Freedom to Marry, will meet with embassy officials, local business leaders and activists this month in Austria, Switzerland and Germany.

“What makes me really proud is that after years of fighting with our government to get to the right place, our government is now able to be a clear, strong voice around the world in favor of human rights,” Wolfson told the Guardian.

The US supreme court made same-sex marriage legal nationwide in a landmark June ruling. Freedom to Marry was one of several mainstream organizations credited with catalyzing the final legal battle after decades of activism across the country.

Wolfson said he received a congratulations call from Vice-President Joe Biden after the supreme court ruling was announced. Wolfson said Biden remarked how important the decision was for US foreign policy.

“That’s really what he singled out and that’s what I feel like we’re now seeing the real fulfillment of,” Wolfson said.

In Switzerland, same-sex couples can register their relationship but do not have the right to marry. Campaigners there are pushing for a nationwide ballot initiative to secure that right.

Germany offers same-sex couples the option to enter a civil partnership, but not the right to marry.

Austrian lawmakers showed a strong opposition to same-sex marriage a week before the US ruling was announ Of the country’s 136-person national assembly, 110 representatives voted against a resolution to make same-sex marriage legal.

Energy for the global movement to make same-sex marriage legal grew in May, when Ireland voted by a huge majority to legalize same-sex marriage. It continued through June with the US decision.

Wolfson said that the point of the discussions and speeches abroad is not for the Americans to come in and make same-sex marriage legal in other countries, but to provide information that local activists can adapt to make it legal on their own.

He has already received questions from around the world about things like how to organize, work across the political spectrum and to respond to the opposition’s tactics.

“We’ve had decades of debate and struggle and battles here, so we’ve learned a lot,” Wolfson said. “There are answers to questions people from other countries might have.”