President Bush said yesterday that Soviet economic reforms "have to be in place" for the United States to consider providing economic aid, but he would not object to Washington's western allies sending emergency assistance to Moscow.

With many of the most difficult reforms to create a Soviet market economy yet to be implemented, Bush's comment suggests he has rejected any direct U.S. aid to Moscow for now.

Administration officials said Bush has received a set of options from advisers for additional "technical" assistance the West could provide to the Soviet Union as it struggles to shift from a command to a market economy.

On other topics in a White House news conference, Bush said he is "concerned about a deadlock" in the Middle East peace process, but declined to respond to a detailed letter he received this week from Israeli Prime Minister Yitzhak Shamir. Although officials have described the letter as rejecting U.S. conditions for peace talks, Bush said he hoped to "find some material in the response that permit us to get these talks going again."

Administration officials said this referred to some ambiguity in Shamir's comments on Palestinian representation in future talks with Israel.

"I think there has got to be discussion with Palestinians, and that has to happen, and we will push and find ways to make it happen if we can," Bush said.

He added that "if we get totally stiff-armed" on this approach, "then we go back to the drawing board, because we're not going to sit here and do nothing."

Later, the Israeli Embassy here released a statement from Shamir saying he "believes that there is enough room to proceed together with the United States to reach an agreement on a common approach" to the peace process.

Shamir's statement appeared to be a response to news reports that he had rejected U.S.-backed conditions for talks between Israel and Palestinians.

Clovis Maksoud, permanent observer of the League of Arab States to the United Nations, appealed to Bush to support a U.N. international peace conference, which the United States has rejected in the past.

On Soviet aid, officials said Bush may present to the other leaders at the economic summit in Houston one or more of the options for "technical" aid he has been given. West German Chancellor Helmut Kohl, with an eye toward easing Soviet concerns about the unification of Germany, recently proposed a $15 billion western aid package for Moscow.

Leaders of the European Community meeting in Dublin recently referred Kohl's idea to a study group, and U.S. officials said the Houston summit may produce a parallel effort.

"I've tried to be very up front, not only with the allies but with the Soviets on the difficulties we have at this juncture, because there has got to be economic reform there, market reform, and all kinds of changes that I believe {President Mikhail} Gorbachev wants to see take place," Bush said. "But they have to be in place for the United States to go forward."

Bush added that Americans may balk at putting "X-billions of dollars . . . into the Soviet economy when it's not reformed, when they're spending 18 percent of their gross national product on military and when they're spending an estimated $5 billion in Cuba. Some of our allies might not be as concerned about that last point as we are. I'm very concerned about it."

Bush noted that the new European development bank being set up provides "a facility for future lending."

But under restrictions sought by the United States, the Soviet Union can receive aid equivalent only to the amount of Moscow's contribution to the bank. This provision is locked in for three years.

Said the president of Kohl's proposal: "I want to talk to them about it, but I don't think we should . . . tell Mr. Kohl what his lending policy, or finance policy should be." Bush added, "He's a neighbor; they've got quite different problems with the Soviet Union than we do."