President Reagan told Congress yesterday that he will seek a $2.67 billion supplemental authorization in fiscal 1984 for direct loans by the Export-Import Bank "if necessary to meet subsidized foreign officially supported competition."

This would be in addition to regular direct-loan authority of $3.8 billion--unchanged from fiscal 1983--and a boost from $8 billion to $10 billion in commitments to Ex-Im Bank guarantee and insurance programs, which would be used mostly to meet demand for credit from Third World countries.

The proposed beefing-up of the Ex-Im Bank is part of a broader commitment by the Reagan administration to its international economic responsibilities.

In the State of the Union address last week, Reagan had set the tone when he said "we must . . . recognize that our economic well-being is inextricably linked to the world economy." He added that the theme of the economic summit, which he will host this May at Williamsburg, Va., will be "to lead the way toward freer trade."

In his budget message, Reagan said yesterday that "our foreign policy is oriented toward maintaining peace through military strength and diplomatic negotiation; promoting market-oriented solutions to international economic problems; telling the story abroad of America's democratic, free-enterprise way of life; and increasing free trade in the world while assuring this country's equitable participation in that trade."

Overall, less than 2 percent of the budget is devoted to international programs, including those defined as military assistance for international security purposes. The new budget calls for $13.2 billion in spending on international programs, up modestly from $11.9 billion in outlays in fiscal 1983. About half of this increase, or $600 million, is for economic and military security assistance.

For strictly economic or financial assistance abroad that is not connected to security needs, the budget calls for an increase of only about $150 million in fiscal 1984, most of which would be for the multilateral development banks, including the World Bank.

As indicated earlier, the budget requests a supplemental appropriation of $245 million in fiscal 1983 for the International Development Association, and an additional budget authority of $1.1 billion in fiscal 1984 to complete the U.S. commitment to the IDA-6 lending program.

All told, the budget asks for $1.6 billion in new authority for the development banks in fiscal 1984, and an additional $2.9 billion in callable capital contributions, pledges on which they can draw if needed.

The budget is not specific on the prospective additional U.S. commitment to the International Monetary Fund, which the president singled out in his budget message as needing more resources "to help bring the world economy back to strong, noninflationary growth."

But the president promised to submit a request for authority--which does not have a net drain on the budget--for the U.S. share of a new overall IMF quota, or deposits by member countries, "in a range equivalent to $93-$100 billion, and an expansion of the General Agreements to Borrow (GAB) to $19 billion." The added U.S. help for the IMF and GAB--a fund provided by rich nations for use by the IMF--does not result in net budget outlays, because the United States gets a corresponding increase in monetary assets (special drawing rights, or SDRs).

The exact overall IMF quota increase is scheduled to be decided at a meeting here Feb. 10 and 11 of the IMF's Interim Committee.

Last year, the administration had brushed off the business community's warnings that the Export-Import Bank was financed inadequately with a comment in its Budget message that the Carter administration had allowed the bank to grow too fast. Carter's direct loan figure of $4.4 billion for fiscal 198 was cut to $3.8 billion. But the administration now appears convinced that the stringency has hurt American exports.