Gas prices pushed toward the $3.50 mark in the past week, and analysts say they aren't expected to retreat any time soon.

The average in metro Atlanta on Monday morning was about $3.47 per gallon, according to atlantagasprices.com. That's the same as the national average compiled in the weekly Lundberg Survey.

That's up from $3.36 a week ago and $3.21 a month ago.

Nationally, regular gas is up 60 cents from a year ago.

The national average price for a gallon of diesel is $4.21. That's $1.24 more than a year ago.

Of the cities surveyed, the cheapest price is in Newark, N.J., where a gallon of regular cost $3.21, on average. The highest was in San Francisco at $3.88.

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