HOUSTON, June 11 — The Enron Corporation has agreed to pay nearly $30 million in additional severance to about 4,200 former employees who were laid off after the company filed for Chapter 11 bankruptcy protection last December.

The company said today that after long negotiations it had reached a tentative agreement with the largest creditors in the bankruptcy case and a group of former employees who had been pressing the company for a larger severance package.

The proposal is expected to be filed with the bankruptcy court in the next few days. If the federal judge in the bankruptcy case approves the deal, Enron will pay former employees up to $7,900 in additional severance. Many former employees have already received as much as $5,600 in severance pay.

According to Enron's severance program, a laid-off employee would have been entitled to about a week's pay for every year of service and a week of pay for every $10,000 in salary, said Mark A. Palmer, a company spokesman.

Because of the bankruptcy filing, Enron officials said they were unable to even approach making such large severance payments.

A group of former Enron employees, however, declared victory today after months of pressing the company to further compensate the thousands of employees who were laid off after the company collapsed.

"This is a good deal for former employees," said Richard Rathvon, a former Enron worker who is co-chairman of the employee committee in the bankruptcy case. "But this is just one issue."

Enron and its creditors also agreed to allow the employee committee to investigate and try to recover some of the huge retention bonuses the company paid to some high-level employees just ahead of the bankruptcy filing last December.

Enron may have paid as much as $100 million in retention bonuses just before it filed for bankruptcy protection. The employee committee, which was appointed by the bankruptcy trustee, thinks the retention bonus process was unfair and that some employees left the company soon after accepting the money.

Former employees said their effort to win larger severance packages was bolstered by the Rev. Jesse Jackson; Representative Sheila Jackson-Lee, a Democrat from Houston; and the A.F.L.-C.I.O. The coalition helped organize former employees in the wake of Enron's downfall and has held several town hall meetings nationwide in recent months.

Today, Mr. Jackson, Ms. Jackson-Lee, several former Enron employees and a small group of placard-waving A.F.L.-C.I.O. members held a news conference in a park across the street from the Enron corporate headquarters in downtown Houston.

"Enron workers demanded what was rightfully theirs and did not take no for an answer," said Linda Chavez-Thompson, executive vice president at the A.F.L.-C.I.O. "They were victimized and they have now triumphed over corporate greed."

Mr. Jackson said that over the last few months he had pressed Kenneth L. Lay, Enron's former chairman, and Stephen F. Cooper, the acting chief executive, to help win additional compensation for workers who had been laid off. He applauded their cooperation.

Now that an agreement has been reached, Ms. Jackson-Lee said there could be momentum on Capitol Hill to create legislation intended to help protect workers in the event of a bankruptcy.

"There could be legislative action making employees secured creditors," she said.

If the severance agreement is approved by Judge Arthur J. Gonzalez, who is presiding over the bankruptcy case in New York, former employees would be given the option of accepting a severance package worth up to $13,500 in total or pursuing their own legal remedies.

Katherine Benedict, a former employee who has been searching for a job for six months, said she was pleased with the outcome. She had worked at Enron for seven years.

"This is a very happy day," Ms. Benedict said. "It was the money I should have gotten. I was out of work for six months.

Ms. Benedict, 34, said she recently found a job in Houston. She starts on Wednesday.