 During his time in Parliament, Jenkins was a contributor to debates concerning industrial questions and Welsh issues.He did not fight again a Parliamentary election again until 1936 when he stood as the candidate of the National Government with the support of the local Liberal and Conservative parties  under the description National Liberal at a by-election in Llanelly.He did not win the seat however which was held for Labour by Jim Griffiths the president of the South Wales Miners' Federation with a majority of 16,221 votes, virtually unchanged since the 1935 general election.