NEW YORK, March 19 (Reuters) - ExxonMobil ( XOM ) filed

a protest notice on Wednesday asking regulators to block

Colonial Pipeline's proposed changes in fuel shipping terms,

citing potential harm to shippers and consumers, a filing

showed.

The Colonial Pipeline is a key artery for shipping fuel from

the U.S. Gulf Coast to the East Coast, where refining capacity

has shrunk and pipeline shipments are the most cost-effective

way to meet regional demand.

Earlier this month, Colonial sought approval from the

Federal Energy Regulatory Commission (FERC) to stop shipping

different gasoline grades at the same time, and to eliminate

shipments of so-called Grade 5 gasoline.

The pipeline operator said the changes would streamline its

operations and minimize slowdowns.

"Colonial's proposed tariff changes will severely disrupt

the efficiency of the gasoline supply chain," Exxon said in the

protest notice.

A Colonial spokesperson said the company would respond to

Exxon's filing shortly.

If the changes are approved, shippers will not be allowed to

ship gasoline products with higher Reid Vapor Pressure, or RVP,

but Colonial can deliver the products to downstream markets.

Exxon said the proposed changes benefit Colonial but harm

the margins for everyone else involved in the supply chain.

Several gasoline marketers who spoke to Reuters on condition

of anonymity earlier this month said they were exploring options

for court challenges if Colonial follows through with the

changes, Reuters reported.