Manny Pacquiao has been stepping up his training in the Philippines as he readies himself for the final fight of his career against Timothy Bradley in April.

The 37-year-old has been training at a sports complex in the city of General Santos as he gets ready for his first return to the ring since being beaten by Floyd Mayweather last May.

Pacquiao and Bradley have met twice before, with the US fighter winning the first fight by split decision in 2012, before Pacquiao got his revenge by unanimous decision in 2014.

Manny Pacquiao has been stepping up his training as he prepares for the final fight of his career

Pacquiao will go up against Timothy Bradley at the MGM Grand in Las Vegas in April

Pacquiao training at Pedro Acharon Sports Complex in General Santos, Philippines on Thursday

Pacquiao has been getting ready for his first return to the ring since being beaten by Floyd Mayweather

In the build-up to the bout, Pacquiao has insisted that clash at the MGM Grand will be his last as a professional. 'I'm so happy to be hanging up my gloves after this fight,' he said last week.

However, his promoter Bob Arum has refused to rule out a return for the Filipino fighter in the future, despite the fact he is set to run for a seat in the Philippines' senate later this year.

'Once that bell rings for that final round, Manny Pacquiao's going to rethink it and who knows if he decides to return?' Arum said.

'I've been in this boxing business for 50 years and I know that fighters retire and other than, say, Rocky Marciano, they come back.

'Will it be Manny's last fight? I'm not ready to guarantee that.'

A crowd of locals watches on as Pacquiao goes through some drills during his training session

Pacquiao has insisted that clash at the MGM Grand will be his last as a professional

Pacquiao also unwound with a friendly game of volleyball during his training session

Pacquiao dribbles two basketballs at the same time in front of a small crowd of onlookers

And, despite the retirement of Mayweather last year, Arum has also said he is hoping to see a rematch of the richest fight in history between the American and Pacquiao at some stage.

'I'd love to see a Mayweather-Pacquiao second fight, of course I would,' added Arum. 'The first fight was by far the most lucrative in the history of boxing.

'But Mayweather has to un-retire, Manny has to decide whether or not he's elected to the senate and he'll do the rematch, so we'll have to see.