Paris rubbish collectors could strike over the summer, a major French union said Thursday, raising the spectre of piles of stinking trash on the streets during the Olympic Games.

Walkouts could start in May and continue from July 1 to September 8, the CGT union branch representing binmen warned, a period that includes the Games, which run from July 26 to August 11.

Refuse workers in the Paris region are demanding an extra 400 euros ($430) per month and a one-off 1,900-euro bonus for those working during the Olympics.

"We're going to be giving it our all and we want that taken into consideration," Nabil Latreche, a member of the CGT-FTDNEEA union, told AFP.

"The municipal police are getting a bonus and we have the same employer. We're going to have an excessive workload too with the 15 million tourists that are expected," Latreche said.

Paris city hall had discussed offering graduated bonuses for rubbish collectors, ranging from nothing up to 1,200 euros, he added.

The mayor's office told AFP an April announcement of bonuses of between 600 and 1,900 euros for workers contributing to the Olympics effort would extend to refuse collection as well.

The CGT walked out of talks on learning the level of payouts would be dependent on how much extra work people had to take on, city hall added.

A meeting between Paris deputy mayors and the CGT is slated for next week.

Some rubbish collectors had had to cancel holidays as there were no additional staff recruited, Latreche said.

Binmen already walked off the job on April 24 but received no concessions, the trade unionist told AFP.

In March last year, a three-week strike by rubbish collectors against President Emmanuel Macron's unpopular pensions reform saw more than 10,000 tonnes of waste piled in Paris streets at its height.

Images of the heaps of trash, some mounting several metres high, were seen around the world.