Copenhagen — Denmark will have its first Conservative leader since 1894 when Poul Schluter , Conservative Party chief, is sworn in as prime minister of a nonsocialist minority coalition government.
Denmark's ruling Social Democrats resigned last week after failing to receive parliamentary support for a controversial economic package aimed at trimming about $1.25 billion from the nation's $12 billion deficit.
Prime Minister Anker Jorgensen was unable to win support from the parties further to the left - the Socialist People's Party, the Left Socialist Party, and the Danish Communist Party. They objected to cutbacks in Denmark's elaborate social-welfare system, while the parties on the right refused to accept new taxes on insurance companies and pension funds.
Only two months ago leading European social democratic leaders came to Copenhagen for Mr. Jorgensen's birthday, congratulating him as the world's longest-standing social democratic leader. Since he came to power in 1972, however, the party has grown increasingly cooperative with the conservative parties.
Mr. Schluter, a lawyer, has formed a minority coalition involving his own Conservative Party as well as the Center Democrats, Christian Democrats, and the unsuitably named Left Party. At the same time he will be able to count on the support of the centrist Radical Liberals as well as the extreme-right Progress Party, which was too controversial to embrace in the coalition because of its opposition to taxes and welfare.
Schluter is expected to be more enthusiastic about NATO and more accepting of nuclear weapons than his predecessor. He will most likely be more staunchly anti-Soviet and more understanding of President Ronald Reagan's economic policies.
The White House has been unhappy with the Jorgensen administration's criticisms of American policy on armaments and El Salvador. Schluter, however, is unlikely to propose drastic changes in the month ahead for fear of provoking a premature parliamentary crisis that would lead inevitably to a general election.
His first priority will be to reduce the national deficit and remove Denmark from the International Monetary Fund's blacklist, where it appeared for the first time last week.
Political observers generally agree that the Social Democrats would welcome some time as the opposition party to reorganize their ranks. While the party's annual conference last weekend rallied behind Jorgensen's leadership, there is a feeling that the party will move back to the left in a number of policy areas. In a speech to the party faithful, Jorgensen made an unlikely paraphrase of Churchill when he said that he was resigning because Denmark was not ready for ''blood, sweat, and tears.''
Denmark currently presides over the European Council under the six-month rotating leadership system. No major upheavals are expected in Brussels as a result of the new Danish administration. A similar situation occurred during the Danish presidency in 1973. The Italian presidency has also occasionally coincided with a change of government.
More significant may be the influence that the Danish parliamentary crisis has on Sweden, where the Social Democrats have been expected to oust the Centrist government in the general election Sept. 19.