WASHINGTON--President Reagan, casting a skeptical eye upon moves toward peace in Central America, wants renewed Contra aid as an "insurance policy" against backsliding by Nicaragua, his spokesman says.

Reagan was to discuss his plan for supporting the Contra rebels yesterday in a speech being billed by aides as a major policy address before the Organization of American States.

The president planned to "emphasize his support" for the regional peace plan unfolding in the region, said his spokesman, Marlin Fitzwater.

But Reagan also was to relay his concerns about the regional accord and discuss his Contra request "as an insurance policy for implementation" of the agreement, the press secretary said.

Fitzwater said the president does not intend to issue "final judgments" about whether Nicaragua's leftist Sandinistas are complying with the peace accord.

"We just cast a skeptical eye and say, `Watch,''' he said.

The speech came as House Speaker Jim Wright warned that no proposal for military aid is likely to get congressional approval as long as the peace process continues.

"I don't see any necessity for sending anyone military money while the peace process is going on," the Texas Democrat told reporters.

In recent days, Wright has accused Reagan of attempting to "torpedo" the peace process by making unrealistic demands of the Nicaraguans to appease "the extreme right wing.''

Wright and Reagan agreed in August that any military aid request would be postponed until after Oct. 1 as long as Nicaragua took certain steps toward democracy.

Their plan was superceded by a regional agreement signed by Nicaragua and four other Central American nations. It calls for certain steps towards democratic reform and a cease-fire, to be implemented by Nov. 7.

Reagan has derided that plan as "fatally flawed," while Wright has urged that military solutions be put aside to allow it time to flower.

On Tuesday, Fitzwater said Reagan may put his funding request before Congress prior to the Nov.7 deadline.

Last month, Secretary of State George Shultz said the administration intended to seek $270 million in military and humanitarian aid for the rebels over 18 months.

Fitzwater denied that Reagan has arrived at a new set of guidelines--beyond those included in the regional plan--that would be used to judge Nicaragua's compliance with the peace accord and determine whether to send further Contra aid.

The peace proposal Reagan and Wright agreed to in August would be cited "as a way of judging" the peace process, Fitzwater said.

The spokesman said the administration believes the plan "has flaws,'' but he also praised it as a "dynamic plan...that can work and is working in many respects."

He also noted, however, that the plan should be seen as "an impetus to other kinds of movement on the part of the Sandinistas," and that it contains "loopholes...that we are concerned about."