Less than 24 hours after beating Keith Thurman in a welterweight championship fight, Manny Pacquiao boarded a private jet bound for the Philippines to try and attend the State of the Union.

Pacquiao is a senator back home in the Philippines -- and has previously floated the idea of running for President one day.

And, with this being a crucial week in terms of Filipino politics, Manny knew he couldn't waste time celebrating his victory in Las Vegas.

A rep for Pacquiao tells TMZ Sports ... "He left at 6 p.m. PT [Sunday] via private jet. One stop in Anchorage than straight to Manila."

Unfortunately, Pacquiao didn't make it back home in time for the SOTU -- but he's hoping to participate in other important Senate functions this week.

FYI, Manny reportedly made at least $10 million for the Keith Thurman fight ... with the potential to make a lot more based on pay-per-view buys and other factors.

After the fight, multiple senators in the Philippines issued official statements congratulating their colleague ... including Senator Sonny Angara who said:

"One solid win by Pacman, one giant celebration for his countrymen. This vintage Pacquiao win shows why his people love him to the moon and back."

"By Monday, my friend and colleague will step again into the Senate ring to join the fight against our ancient enemies - hunger, joblessness, poverty. Expect him to the bring the same spunk he had shown in boxing to this unfinished fight of his life."

Sen. Cynthia Villar said ... "I join the Filipino community around the world in celebrating the victory of our Pambansang Kamao, Manny Pacquiao."