Climate change activists on the election trail have a new ally in combating Republican nominee Donald Trump: Planned Parenthood.

Billionaire climate activist Tom Steyer, joined by labor unions, codified a relationship Tuesday with the women's health and abortion provider in stepping up an anti-Trump campaign in New Hampshire, where Republican Sen. Kelly Ayotte is fighting a tough re-election battle against Democratic Gov. Maggie Hassan.

"We have a historic opportunity this year to elect progressive leaders to the White House and the Senate," Steyer said. "That's why our partnership with [the Service Employees International Union] and Planned Parenthood Votes is so crucial as we work to empower New Hampshire voters to make sure their voices are heard this November."

Steyer said the right to have an abortion and the fight against climate change are linked in the cause of defeating Trump and his allies in the Senate in November. "Whether it's on climate change, economic opportunity or access to reproductive healthcare, a Trump presidency and Senate ally in Kelly Ayotte would be a disaster for working families," he said.

"Our task is clear: we must stop Dangerous Donald and take back the Senate — and there's only one way to do it: vote."

"This partnership was a no-brainer," said Dawn Laguens, who heads Planned Parenthood Votes, the group's political arm. "When you look at the patients who come into Planned Parenthood health centers, these are the issues that affect their lives: they need access to health care. They want to be paid a fair and equal wage. Their communities too often face the worst impacts of anti-environmental policies.

"In this election, we've seen Donald Trump use a sexist, racist, anti-worker and anti-environment message to try and reach voters," she added. "That's why we've built this coalition, and are working together at an unprecedented, election-changing scale." The groups have contributed $2 million to fighting Trump and Ayotte in New Hampshire.

Planned Parenthood came under heated controversy last year when anti-abortion activist David Daleiden released videos showing Planned Parenthood officials discussing the harvesting and donation of aborted fetal body parts.

The videos prompted a Republican-led effort to defund the group, with House Republicans forming a special investigative committee on fetal tissue donation.