The editorial page of The Jewish Press quotes at length from R. Ahron Soloveichik and R. Mayer Twersky regarding relating to people who are intermarried (link):
In early 1992, reacting to alarming statistics on the occurrence of intermarriage (52% as compared to 9% in 1965), a splinter group of rabbis in the Rabbinical Council of America, who earlier had formed what was called the “RCA Roundtable,” proposed that instead of “writing off” intermarrieds and driving them away, “we must respond constructively to the future of Klal Yisrael in the next generation” and “explore the full range of possible responses to this phenomenon.”...Continued here
The Roundtable proposal created something of an uproar – not in small part because it ran counter to the well-known views of the great gaon and spiritual mentor of Modern Orthodoxy, Rav Yosef Dov Halevi Soloveitchik, zt”l – and was ultimately rejected by the RCA.
The run-up to the RCA’s rejection of the proposal was fascinating. No fewer than fourteen leading roshei yeshiva of the Rabbi Isaac Elchanan Theological Seminary (RIETS), including Rav Dovid Lipschitz (the Suvalker Rav), zt”l; Rav Aaron Soloveichik, zt”l; and, ybd”l, Rav Moshe Dovid Tendler and Rav Dovid Bleich, signed a statement denouncing the Roundtable’s proposal as inconsistent with halacha.
Also, on April 15, 1992, on official RIETS stationery, Rav Aaron Soloveichik sent a letter to the RCA, of which he was a leading member, explaining why the proposal should be rejected.