Spain approved an emergency measure on Tuesday designed to help domestic workers who have seen their work hours reduced, temporarily suspended or been fired since the country went into lockdown due to the coronavirus pandemic.

Domestic workers registered with the state's social security services will be able to claim 70% of their base salary for one month if they can prove their hours have been cut or they have been fired since the lockdown began on March 14.

It is the first time domestic workers in Spain - the majority of whom are women - have had the right to unemployment benefits, although the offer is still less than for other sectors.

"The domestic service sector, often invisible, has suffered hard from this health crisis," the Ministry of Labour tweeted on announcing the new measure.

"Today the government is extending protection to more vulnerable workers in our country."

Workers' rights groups in a number of other countries in Asia and Latin America have flagged that the coronavirus pandemic increases the fragility of many domestic workers' jobs.

According to official figures, there are about 600,000 domestic workers in Spain, but human rights groups say there could be up to 200,000 more operating through the black market. Most are Latin American migrants.

In Spain, it can take up to three years for migrants to receive a residency permit during which time they are not allowed to work so many turn to informal jobs.

Carolina Elias, president of Madrid's Domestic Service Association (SEDOAC), said it was a good move for domestic workers in Spain, who traditionally receive considerably less state protection than in other European countries.

"Up until now domestic workers have been left totally unprotected ... so this is progress," she told the Thomson Reuters Foundation by phone.

But she said the impact would be limited because about 40% of domestic workers in Spain operate on the black market and one month's subsidy was not enough.

Spain's lockdown rules - among the strictest in Europe - prevent people going out unless they need to buy food or medicine or are essential workers, meaning many families have suspended or fired staff as they are at home to do the jobs.

Others are concerned about money or do not want to force someone to travel to work thereby risking them catching and spreading coronavirus, said human rights groups.