WASHINGTON (AP) - Congressional Democrats are forcing the Yucca Mountain nuclear dump in the home state of Senate Majority Leader Harry Reid to get by on its lowest annual budget in years, likely causing yet more delays in opening the first national repository for radioactive waste.

A year-end spending bill moving through the House and Senate this week would give $390 million to the Nevada nuke dump in the 2008 fiscal year, $104 million less than President Bush requested.

Edward F. "Ward" Sproat, the Energy Department official in charge of the planned dump, warned last week that such a cut would be "very serious" and could push back the date when the Energy Department can submit a required construction license application for the dump 90 miles northwest of Las Vegas.

Sproat has promised repeatedly to submit the license application by June 30, 2008, and his best-case scenario for opening the dump is 2017. The opening date had already been expected to slip by several years and the license application date now also appears in jeopardy.

The ultimate fate of the planned dump, meant to contain 77,000 tons of radioactive waste piling up in 39 states, is growing increasingly cloudy. The leading Democratic presidential candidates all oppose it.

"I am proud that I was successful in cutting $104.5 million from Yucca's budget," Reid, D-Nev., said in a statement Monday. "It is clear that the Yucca Mountain project is a dying beast and I hope that this cut in funding will help drive the final nail into its coffin."

Yucca Mountain was originally supposed to open in 1998 and taxpayers are facing legal liability expected to exceed $7 billion because the government contracted to begin accepting spent fuel from nuclear plants that year.

The 2008 budget number is paltry even considering that Bush has repeatedly gotten less than he wanted for the waste dump because of Reid's opposition, now given more force because Democrats are in the majority.

Last year the dump's budget was $444.5 million. It hasn't been below that since 2002, the year Congress approved the site.

Recognizing the delays afflicting Yucca Mountain, legislative language accompanying the spending bill also directs the Energy Department to develop a plan to take custody, at one or more interim sites, of spent nuclear fuel now at decommissioned reactor sites. According to the Nuclear Energy Institute, there are 13 such sites in nine states holding at least 3,000 tons of nuclear waste.