THE REAGAN administration is proceeding toward negotiations with Nicaragua in a strange way. Having renewed its offer to discuss the eight points it raised last summer, it is holding back from opening talks. Officials suggest it would help if the Sandinistas stewed in their juice a bit more and even if they worried whether Washington might be aiding their political foes. Until the United States can verify that Managua's support for the guerrillas in El Salvador slows, it is said, the administration will simply "study" the scene.

A similar twist is evident in the administration's dealings with Cuba. Evidently dissatisfied with their contacts with the Reagan team so far, the Cubans have been reaching out to other Americans to advertise a readiness for wide-ranging negotiations. They have reportedly dropped their longtime insistence that the United States start by ending its general embargo on trade with Havana. In seeming response, the administration this week took up one of the few pieces of slack in the embargo by reimposing certain currency restrictions--a move likely to cut travel to Cuba by American tourists and businessmen. The reason given was to reduce Cuba's earnings "at a time when Cuba is actively sponsoring armed violence against our friends and allies."

There is the hint of a pattern in the official reaction to the interest in negotiations expressed by the two Marxist regimes. The United States appears to be setting as something of a precondition--the end of military-aid operations--what one might have expected to be on the table in talks. The administration is upping the ante in a way that seems almost calculated to embarrass those in the Nicaraguan and Cuban leaderships who may have argued in favor of giving negotiations a try.

There is a rationale for playing hard to get. It is that the Nicaraguan and Cuban regimes are on the ropes and the United States can get a better deal by pushing hard; meanwhile, those regimes must be disabused of the notion that they can play the harmonica of American public opinion and wring concessions from the American government for free.

If this is the administration's tactic, however, it is not using it very smoothly. It risks conveying the impression that it would prefer negotiations to fail so that a harder policy could then be tried. We trust the administration has nothing like that in mind. Such is the history of tension and misunderstanding between the United States and the two Caribbean places that no one can be sanguine about negotiations. Surely, however, the administration is not so lacking in confidence or capacity that it cannot sit down with Managua and Havana and give talks a fair chance.