UPDATED -- The average cost of diesel has fallen below the $4 per gallon mark for the first time in a little over a month, according to new figures from the U.S. Energy Department, while gasoline has seen its seventh consecutive weekly increase.

It is down 1.5 cent from a week ago, hitting $3.988 per gallon. Compared to a year ago it is 1.8 cent less.

Prices fell in all regions of the country over the past week, with the largest being seen in the New England and Central Atlantic sections, down 3.4 cents and 3.7 cents, respectively, while the smallest was in the Gulf Coast region, 0.3 cents less.

Also, the New England and Central Atlantic areas, which make up two of the three subsections of the entire East Coast region, are just two of four parts of the country where prices are higher compared to a year ago. New England is up by 10.8 cents; Central Atlantic by 16.8 cents; while the East Coast is 6.5 cents higher and the Rocky Mountain region is 4.9 cents more.

Diesel ranges from a high of $4.279 in New England to a low of $3.80 in the Gulf Coast region.

In contrast, gasoline moved slightly higher over the past week, edging up 0.2 cent, for an average $3.549 per gallon, its highest price since last September.

Price increased in all regions, except in the Midwest, where it fell 2.3 cents, averaging $3.551, along with drops of half a cent or just barely more in the New England and Central Atlantic parts, averaging $3.598 and $3.588, respectively.

Gasoline ranges from an average of $3.823 in the West Coast region to a low of $3.319 in the Gulf Coast region.

As for oil it edged higher by 14 cents on Monday, settling at $99.60 per barrel in New York, as the market weighed the possibility of crude supply disruptions stemming from Russia’s invasion of Ukraine and the closure of the Houston Ship Channel on Saturday following a crash between two vessels.

Compared to a week ago oil is up around $1.75 per barrel after briefly going past $100 last week, due to tensions over Ukraine and the U.S. and other Western nations putting sanctions on Russia. 

Update adds gasoline prices.