British Foreign Secretary Lord Carrington announced tonight that he will travel next week to Pakistan, Turkey, Oman and possibly other countries near Afghanistan to assess their reaction to the Soviet invasion of Afghanistan.

"I want to see what they feel, to see what they think," Carrington said, "and to let them know of Western support for them."

Carrington indicated that he was making the trip on behalf of the NATO nations that have been coordinating their response to the Soviet action with the United States. He said he wanted this response to place "emphasis on the nonaligned countries" because they are "getting worried" and he hoped they "will take issue with the Soviet Union about this."

He said in a nationally televised interview that the Western world must "make it abundantly plain to the Soviet Union that we won't tolerate any more of this. The Russians might have thought that after some days or months the world would forget about Afghanistan. It is up to us to make sure they don't forget."

Carrington said he and Prime Minister Margaret Thatcher had "found totally unconvincing" the explanations made to them today by the Soviet Ambassador here, Nikolai Lunkov, at a stormy 40-minute meeting at 10 Downing St. Carrington characterized as "just too childish" Soviet assertions that Kabul requested Soviet assistance because other governments were interfering in Afghanistan.