Pepco and its union have struck a preliminary agreement, probably averting a strike, the utility and union officials said Monday.

Pepco spokeswoman Myra Oppel said the agreement still needs to be approved by the members of the union, International Brotherhood of Electrical Workers Local 1900. IBEW Local 1900 president James A. Griffin said the vote is likely to occur next week.

The agreement was struck Sunday night after extensive negotiations over the weekend, Oppel said. Both Oppel and Griffin declined to provide specifics on the contract, but Griffin said he would release a memo detailing the agreement later this week.

“I’m grateful for the support the membership gave us during this difficult time,” Griffin said. The union leadership “will be recommending that the membership vote for this contract. But it will ultimately be up to the membership to vote on it.”

The company and union were at an impasse for months, and officials from both sides said they were worried about a potential strike.

The union raised objections to several provisions in the company’s previous offer, which was rejected 5 to 1 at a union vote last month. Griffin said at the time that his greatest concern was that Pepco wanted to eliminate the union’s ability to arbitrate changes to its health and welfare plans in favor of a different appeal process.

Some analysts Monday praised the agreement. Paul Patterson of Glenrock Associates said there was some concern of a strike because it could cause problems for customers during major weather events.

“For some reason this company hasn’t been exactly lucky” with storms, Patterson said with a laugh. “The last thing we want is another reliability issue.”