The gap between the rich and the poor is widening all the time.
Literal
Wealthy people [and-と] poor people [and-との] gap [topic-は] increasingly widen-[ongoing-ている].
A formal social commentary. The との combines the accompanying-と with the appositional の, used here to link the two groups to the noun 格差 ('gap, disparity'). ますます ('more and more, increasingly') is an intensifier for progressive change. 広がっている ('is widening') captures the ongoing process.