Low-income seniors and those disabled won't face late Medicare fees if they sign up after Monday.

With pressure mounting to extend Monday's enrollment deadline for the Medicare prescription-drug benefit, the Bush administration took another small step in that direction yesterday, waiving penalty fees for very low-income seniors and people with disabilities who sign up late.

Officials determined that collecting the fees from poor beneficiaries would cost more than the penalties themselves.

To be eligible, individual Medicare beneficiaries must have annual incomes below $14,700 and assets worth no more than $11,500. For couples, the income limit is $19,800 and the asset limit is $23,000.

The move follows a recent administration decision to allow the same impoverished beneficiaries to sign up for Medicare drug coverage until Dec. 31.

"In other words, you can apply after May 15 without penalty," President Bush told a group of older Americans in Sun City Center, Fla. yesterday. "And that's important for low-income seniors to understand."

The step does little to quiet the growing call for Bush and the GOP-led Congress to extend the enrollment deadline and waive late fees for the general Medicare population. Seniors joined by Democrats and advocacy groups will stage a protest rally today on Capitol Hill to repeat their demands for those moves.

Despite rumors that GOP lawmakers would seek such changes this week, Bush administration officials oppose the move and urge seniors to enroll before Monday.

Except for the very low-income group, those who wait longer to enroll in a Medicare drug plan will pay a 1 percent penalty per month in premiums for each month that they delay.

The Congressional Budget Office estimates extending the deadline through December would bring in one million more enrollees. But the government would forfeit $100 million in late fees this year, or $3.4 billion over 10 years.

By extending the enrollment period and eliminating late fees for impoverished beneficiaries, Medicare officials hope to encourage applications from low-income people, who need coverage the most but thus far have proved the most difficult to enroll in the new benefit.

Some 7.2 million poor beneficiaries qualify for special coverage that pays more than 95 percent of their prescription-drug costs with minimal or no premiums, low deductibles, and no gaps in coverage.

But only 1.7 million - about 24 percent - have been approved for the subsidized low-income coverage so far. Many of the estimated four million who applied were ineligible because their personal assets exceeded the program's limits.

Monday's enrollment deadline will go down to the wire. Private insurers and Medicare staffers will work until midnight to help seniors sign up before penalty fees kick in.

UnitedHealth Group, which offers the AARP MedicareRX plan, is giving 24-hour phone help through Monday's deadline.