Hun Sen, who has ruled Cambodia for more than three decades, faces a key test at national polls next year with the main opposition party gaining in popularity amid mounting anger over corruption and inequality.
During a speech to more than 10,000 garment workers today, he announced a raft of new benefits for employees, including a commitment to annual pay rises.
The monthly minimum wage for garment workers, currently USD 153, "won't be lower than USD 160" in 2018, he said, adding "the salary will be increased every year".
He also promised a guaranteed pension for the workers from 2019 and said they could travel on public buses for free for two years.
More From This Section
Political analyst Meas Ny said Hun Sen saw the garment sector as a vote bank which was sympathetic to the opposition.
"It is a new strategy to capture their support back," he told AFP.
Hun Sen, 65, has ruled Cambodia for 32 years, tolerating little dissent and skillfully wielding the courts against his opponents.
At the end of his speech, Hun Sen donated USD 5 to each worker attending the gathering and personally handed an envelope of cash to hundreds of pregnant women.
More than 740,000 workers provide the backbone of Cambodia's USD 7 billion textile industry, which supplies brands including Gap, Nike and H&M.
They have been at the forefront of labour protests or strikes for higher wages and have faced several crackdowns by Cambodian authorities.