U.S. gasoline and distillate inventories rose sharply last week as refineries ramped up activity, while crude oil stocks were barely changed, the Energy Information Administration (EIA) said Jan. 4.

Crude inventories rose by 7,000 barrels in the week to Dec. 28, compared with analyst expectations for a decrease of 3.1 million barrels, the EIA said in its report delayed by two days due to the New Year's Day holiday.

Distillate stockpiles, however, which include diesel and heating oil, rose by 9.5 million barrels, the greatest one-week jump since December 2016, the EIA said. Analysts were expecting a 1.6 million-barrel increase.

Gasoline stocks also rose dramatically, rising by 6.9 million barrels, compared with analysts' expectations in a Reuters poll for a 2 million-barrel gain.

In the U.S. Gulf Coast region, gasoline stocks rose to 89.2 million barrels, a new record.

Nationwide, gasoline inventories rose to 240 million barrels, the highest since June, suggesting a glut in U.S. motor fuel has developed during the less active winter.

The gains in product inventories resulted in part from a notable move up in refinery crude runs, which rose by 410,000 barrels per day (bbl/d).

Refinery utilization rates rose by 2.1 percentage points to 97.2%, the highest rate on record for this time of year.

"It's extraordinary that refinery utilization is over 97 percent at this time of year as refiners continue to run full out, supply the domestic market and export significant quantities of product to overseas markets," said Andrew Lipow, president of Lipow Oil Associates in Houston.

Refiners have been running at relatively high rates even during the most recent maintenance period, but seasonal heating oil demand has kept overall inventories of diesel and jet fuel contained.

Oil prices were higher on the day, though the market was already rallying after the Jan. 4 release of monthly U.S. employment data. U.S. crude gained $1.38, or 2.9%, to $48.47 a barrel as of 10:15 a.m. CST (16:15 GMT), while Brent rose $1.44, or 2.6%, to $57.40 a barrel.

Crude stocks at the Cushing, Okla., delivery hub rose by 641,000 barrels, EIA said.

Net U.S. crude imports rose last week by 468,000 bbl/d, while crude production was unchanged at 11.7 million bbl/d.