Labour leader Ed Miliband has said companies which agree to increase the pay of those on low incomes will be offered tax breaks under a Labour government.
However some small businesses are already warning it would still be unaffordable, despite the cuts worth up to £100 per worker.
ITV News Correspondent Neil Connery reports.
More top news
Temperatures tumbling again tonight with a widespread sharp frost and lows of -5C or -6C and icy spots in places
Search teams were again looking for missing airman Corrie McKeague - this time joined by cadaver dogs trained to seek out human remains.
Donald Trump has dismissed pictures showing a smaller turnout to his inauguration compared to Barack Obama's in 2009.