IN A CITY whose residents have been trying for so long to shake off federal control of their local affairs, there must be a certain amount of ambivalence about any congressional or presidential offer of "help" to the District government. A "with-friends-like-these" attitude is understandable, given the federal short-sheeting of the city over the years. Still, when the White House indicates a desire to help Mayor Barry tackle the city's financial crisis, you don't say no thanks.

This time there's a good reason besides municipal poverty to accept the latest White House offer of help. It is coming from administration people who have impressive records of dealing fairly with District affairs. Jack Watson, the new White House chief of staff, and James Dyke, an aide to Vice President Mondale, have met with Mayor Barry and the result will be the rivival of a special task force formed in 1977 to advise President Carter on issues critical to the District.

True, the government is up to its desk tops in task forces that meet, talk, study, recommend and maybe self-destruct, with no measurable impact other than a drain on some agency's budget. But the strength of the District task force is in its makeup. The group is headed by Mr. Mondale and includes the key members of Congress whose committees and subcommittees have specific responsibilities for District affairs, as well as Mayor Barry and Council Chairman Arrington Dixon. If and when these members can agree on a course of action, things can happen.

In the past, the task force made recommendations that brought improvements in the city's pension fund system and aid for St. Elizabeths Hospital, and that resulted in efforts to establish a formula for computing the annual federal payment to the District -- which the White House is now lobbying for on Capitol Hill.

The regrouping of the task force comes on the heels of a request by the Interfaith Council of Metropolitan Washington, representing Protestant, Catholilc, Jewish and Muslim organizations that the Mondale group come up with ways to share responsibility for addressing the city's money matters. White House aide Pauline Schneider notes that "the federal role in District of Columbia affairs has been so consistent and so pervasive that, now, when the District is facing a budget crisis, I don't think the federal government can extract itself and not accept any responsibility." Nor do we.