The House Democratic leadership, moving to tie Reagan administration policies to the 9.4 percent unemployment rate, announced plans yesterday to sponsor a $2 billion jobs program, as President Reagan remained firm on his austerity budget and denounced the Democrats as "obstructionists."

In a day of bitter partisan hostilities, House Majority Leader James C. Wright Jr. (D-Tex.) likened the economy under Reagan to a terminally ill patient, and Sen. Edward M. Kennedy (D-Mass.) described the unemployed as "Ronald Reagan's breadline."

The president shot back: "The single word for that is demagoguery."

As he prepared to board a helicopter at the White House for an afternoon of horseback riding, Reagan said the best way for Democrats to lower the unemployment rate would be to "join us in adopting the budget that was passed out of the Senate Budget Committee."

Rep. James R. Jones (D-Okla.), chairman of the House Budget Committee, countered that the new Reagan-supported budget, which would effectively cut domestic social spending by one-fourth over three years and Social Security by $40 billion, does not stand a chance of passage in the House.

Amid signals of mounting opposition in the GOP-controlled Senate, Jones said, "The plan that is in the Senate at the present will not be able to pass in the House."

A further indication of trouble for the Reagan budget in the House emerged yesterday with a new proposal issued by 10 moderate Democrats and Republicans. The plan calls for tax increases of $145 billion over three years, compared with $95 billion in the administration proposal, and a $52 billion reduction in the growth of military spending, more than double the Reagan figure. It also seeks no reductions in Social Security.

While the budget crisis is producing increasing partisan bitterness, the Democratic embrace of a $2 billion jobs and housing program reflects a growing ideological split between House Democrats and the White House over strategies to deal with the highest unemployment level in 41 years and the prospect of record federal deficits.

With its highly successful attack last year on domestic spending, the administration has placed the federal government in the position of severely cutting back or eliminating basic job and unemployment benefits at a time of deep recession.

The entire jobs-creation section of the Comprehensive Employment and Training Act, which financed 600,000 jobs in 1979, has been wiped out; federal funds for unemployment benefits have been cut back $2.4 billion this fiscal year and face a $4.3 billion cut next year, and trade adjustment assistance, a benefit going to many unemployed steel and auto workers, has been effectively eliminated.

Although largely undefined and modest by past congressional standards, the House Democratic leadership's announcement of the $2 billion program is significant. It represents the first time since the 1980 elections that the party's leaders have supported a new spending initiative to counter economic difficulties.

Until now, Democrats, numbed by the 1980 election results, have generally accepted the GOP premise that the first order of business is a reduction in the size of the federal government.

The Democrats are on a collision course with the administration, which not only stands firmly behind the budget and tax cuts enacted last year but now seeks significantly deeper reductions in social programs while supporting only a slight trim in the rate of the defense buildup.

Sen. John G. Tower (R-Tex.), chairman of the Senate Armed Services Committee, said yesterday that Reagan would permit only a 5 percent reduction in defense growth in 1983.

Reagan is "unwilling to accept any further cut" and "will oppose any effort to go beyond that," Tower said.

While Democrats are now backing federal spending to reduce unemployment, White House aide Edwin Harper told reporters that a new spending program would only increase deficits and work against "turning around the unemployment situation."

The administration policies at a time of rising unemployment provoked sharp attacks from union leaders in different sections of the country yesterday.

AFL-CIO President Lane Kirkland said in Houston: "The president surrounds himself with economic quacks who practice their trade like the leech doctors of old who believe you can cure a patient of all ills by bleeding him to death."

Gerald McEntee, head of the American Federation of State, County and Municipal Employes, told a Michigan group that "the Reagan administration and its supporters in the state have been pulling the rug out from under the average, working American."