Boris Johnson has unveiled £2.5bn of funding for new prison places and given the go-ahead for more police use of stop-and-search powers as he vowed to "come down hard on crime".
The government said the plans showed it was "serious about fighting crime".
But Labour's shadow home secretary, Diane Abbott, said "random" stop-and-search was a "recipe for unrest".
The government's focus on law and order will add to speculation that No 10 is preparing for an autumn general election, said BBC political correspondent Jonathan Blake.
The prison and policing plans for England and Wales follow other recent initiatives from Downing Street about the NHS and immigration.
Last month, the government also pledged to recruit 20,000 extra police officers, nearly replacing the number of officers lost since the Conservatives returned to power.