The federal government will borrow between $45 billion and $50 billion during the next quarter, the smallest amount since $29.8 billion was raised in the second quarter this year, the Treasury Department said yesterday.

For the current quarter, the Treasury said that it plans to sell $17.5 billion in securities to raise $8.3 billion of the $55 billion in new cash it needs by year's end. That would be the largest borrowing since the $56.4 billion during the first quarter of 1983.

Treasury Undersecretary Beryl Sprinkel, who announced the securities refunding, also said that the Treasury Department has asked the Federal National Mortgage Association and other government or quasi-government agencies to put off planned issues of special targeted securities for overseas investors until the Treasury's own recent offering is assessed.

Fannie Mae had considered issuing special securities for foreigners, but had not yet determined the size or date of the offering, a Fannie Mae representative said.

The Treasury last week sold its first issue of the special securities that would allow foreign bond holders and interest recipients to keep their identities hidden from the U.S. government.

Sprinkel said the delay of any issues by other government agencies would be for only a few days.

Sprinkel said the Treasury wanted to be sure not to saturate the foreign markets with U.S. government-backed special securities. "We want to cultivate that market, not kill it."

The Treasury financing brought no surprises to financial market analysts, but "the more important issue is that the totals indicate no further improvement in the federal budget posture is currently taking place," William V. Sullivan Jr., senior vice president at Dean Witter Reynolds Inc., told clients recently.

Interest rates have declined recently -- most notably the prime interest rate, which dropped from the year's high of 13 percent to 12 percent Monday -- as private credit demands have slowed and the Federal Reserve Board has eased its credit position somewhat. However, analysts said that because consumer spending and borrowing may be on the upswing, interest rates might move up later this year.

Although there are signs pointing to continued economic expansion, "this does not mean that $200 billion federal budget deficits do not matter," said Wharton Econometric Forecasting newsletter. "In fact they will be a major reason for gradually rising interest rates over the next two years."

The securities the Treasury will offer next week are:

*A three-year, $6.5 billion note to be auctioned on Monday, a day earlier than usual because of election day.

*A 10-year note for $5.75 billion to be auctioned on Wednesday in minimum denominations of $1,000.

*A 30-year bond for $5.25 billion to be auctioned on Thursday with a minimum denomination of $1,000.

The refunding will also be used to redeem $9.2 billion in maturing debt as well as to raise $8.3 billion in new cash. The Treasury projects a cash balance of $15 billion on Dec. 31, compared with $30.43 billion on Sept. 30.