Senator Robert Kennedy said at Oxford yesterday that the next three or four weeks could be “critical” in the attempt to achieve peace in Vietnam.

He told students in the Oxford University Union that a peaceful solution would be brought nearer if there was some sign from Hanoi of a willingness to cut down on men and equipment going into South Vietnam.

“I think there are some signs that Hanoi is considering its position,” he added.

Earlier, Senator Kennedy was greeted with boos and anti-American slogans, having unwittingly timed his visit to Oxford to coincide with the middle of a student-organised “Vietnam week”. But he won a standing ovation after speaking in the packed Union hall.

Senator Kennedy is one of a group of Senators and Congressmen who have been invited to Britain by the Ditchley Foundation for informal talks with British economic and political experts on the future of Europe and the Atlantic Community.

The talks, at Ditchley Park, Oxfordshire, started on Friday and end tomorrow.

Among British representatives are Lord Beeching, Mr Jo Grimond, Mr Emanuel Shinwell and Lord Harlech.