Manny Pacquiao is widely seen as one of the planet's best boxers but his comments on same-sex couples are sure to cause consternation worldwide.

The boxer is due to fight Timothy Bradley Jr in Las Vegas in April in his final professional fight before focusing on becoming a full-time politician at home in the Philippines.

According to AFP, Pacquiao told the Philippines-based TV5; "It's common sense. Do you see animals mating with the same sex? Animals are better because they can distinguish male from female."

Pacquiao's last fight was in May 2015 against Floyd Mayweather. Picture by: John Locher / AP/Press Association Images

Same-sex marriage remains illegal in the Philippines, as it does in most of Asia. Pacquiao is currently running to gain election to the Philippine Senate in May. 

The 39-year-old is currently a member of the House of Representatives in the Philippines, but spends much of his time away from Manilla in preparation for fights. Despite Pacquiao's poor attendance record in the House, he is expected to win the May election due to his ever-increasing popularity in his homeland.