WASHINGTON (REUTERS) - In his weekly address, US President Barack Obama called on Congress to pass a law requiring most companies to give their workers seven days of paid sick leave each year, describing it as a "must have" for most families.

Mr Obama said most families need two incomes today, but some 40 million US workers have no paid sick leave, so they face the choice of going to work sick, or staying home and losing part of their pay.

He said some workers even face the risk of losing their jobs if they stay home when they're ill.

He's calling on Congress to pass a law mandating sick leave for most workers.

In the meantime, he said the US would begin requiring federal contractors to give employees working on new federal contracts up to seven paid sick days each year.

He said the change will make a "meaningful difference in the lives of Americans".