“Papa loves you babies, mahalo for standing by my side,” the actor wrote in his post about the honor

PHOTO: MAINEI KINIMAKA/UN ENVIRONMENT PROGRAMME

Jason Momoa’s kids are his biggest supporters!

On Monday, the Aquaman star, 42, was named the UN Environment Programme’s (UNEP) Advocate for Life Below Water at the UN Ocean Conference in Lisbon, Portugal. Momoa’s daughter Lola Iolani, 14, and son Nakoa-Wolf, 13, attended the special event with their dad.

The actor posted a series of photos on Instagram that showed his kids intently listening to his discussion at the conference.

“With great respect, admiration, and humility, I join the UN family and commit to the critically important work: to manage, protect and preserve the Ocean and all living creatures on our beautiful, BLUE planet,” Momoa wrote. “We must seek to right the wrongs we have done against our children and grandchildren, turn the tide on our irresponsible stewardship, and build momentum for a future where humanity can once again live in harmony with nature.”

Momoa concluded by giving a shout-out to his kids, who he shares with ex Lisa Bonet. “Papa loves you babies, mahalo for standing by my side,” he signed off.

The actor is also stepfather to Bonet’s daughter with Lenny Kravitz, 33-year-old Zoë Kravitz.

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In January, Momoa and Bonet revealed in a joint statement that they were “parting ways in marriage” though “the love between us carries on.” They began dating in 2005 and later wed in October 2017.

The exes said in their statement, “We have all felt the squeeze and changes of these transformational times… A revolution is unfolding and our family is of no exception… feeling and growing from the seismic shifts occurring. And so we share our Family news that we are parting ways in marriage.”

When Momoa posted a series of photos on Instagram from The Batman premiere in New York City in March, he opened up in the caption for the first time about how his split was affecting Lola and Nakoa-Wolf.

JASON MOMOA/INSTAGRAM

“We had a wonderful time in NYC,” he wrote, in part. “Mahalo to the fans and press for being generous and giving us space for the children it’s hard enough separating in the public eye. We appreciate the continued privacy through these times.”

Last month, Momoa and Ambulance actress Eiza González ended their relationship after several months together. A source told PEOPLE at the time that Momoa was trying to keep things more casual, in part, to protect his kids.

“It’s not that he’s not taking it seriously, but with his kids, he’s not going to rush into anything quickly,” the source said. “He had a lot of love for Lisa and there is still a lot of mutual respect there as far as she’s concerned.”