The two speakers were Glenroy Watson from the rail union RMT, who is organising the cleaners on London Underground and José Vallejo Villa, a T&G/Unite member and a leader of the Justice for Cleaners campaign.
Glenroy pointed out that historically laws on immigration control have been passed to meet the economic interests of the ruling class. Changes made to the immigration laws this March allow employers to spot check the passport of any employee.
Given the situation where many black and Asians born in this country might not have applied for a passport, this law can be misused to discriminate against minorities.
He also pointed out that some employers refuse to recognise the emergency national insurance numbers given to immigrant workers but they still deduct national insurance contributions.
"Where is that money going?" he asked. "It has been only in response to strike action that we have taken in last two months, that some employers have admitted that they have made mistakes."
"In the past, we used to go to the churches and places where refugees and migrants go and campaigned in defence of their rights. We need to revisit those tactics. We also need to sharpen our political arguments. People don't arrive here without any skills, the majority of them do have skills. It's ridiculous that their skills are undermined and exploited. We need to have a public campaign explaining this."
Then José gave his experience in organising migrant workers: "I was a union activist in Colombia for 25 years. Initially I was shocked by the unions here. Being a trade unionist is a culture in Colombia.
"The first job I was given was a cleaning job, through which I met other Latin American workers. We began to organise in cafés and other places. Then with the help of the union I begun to organise the cleaners and initiated the Justice for Cleaners campaign.
"In Canary Wharf, the cleaners were afraid to talk to me at first. The majority were getting £4.85 an hour at that time and no sick pay and no pension.
"In July 2005, the cleaners in parliament went on strike, which was a real morale booster. In Canary Wharf one company agreed to pay £5.50. Workers accepted it and then demanded it be raised to £6.75. The companies said they were willing to pay up to £6.25 but they wanted the union out.
"Then came the HSBC strike. These strikes were very important in breaking down the fear that workers had."
In the discussion, a worker from the bakers' union pointed out that in an isolated working environment it is difficult to cut across racism. "We must fight to unite all workers," she added.
Others also pointed out that employers prefer workers from other countries because they can pay lower wages. We need to work towards unionising these workers. Anybody employed in this country should be given proper wages and not discriminated against.