Image caption Ken Skates has been a senior minister since May 2016

Wales' transport minister is being investigated for a possible breach of government rules, over funding for a bus service in his own constituency.

Labour First Minister Mark Drakeford confirmed he had been asked to investigate Clwyd South assembly member Ken Skates under the Ministerial Code.

This sets rules for ministers' conduct.

Plaid Cymru transport spokesman Rhun ap Iorwerth said "people need to know that there is full transparency in the way that funds are spent on bus services".

Mr ap Iorwerth raised the matter during Tuesday's First Minister's Questions.

"With funds so scarce for improving bus services it was no surprise that there was huge disappointment and harsh criticism when it became clear that the transport minister had personally intervened to ensure funding for a bus service in his own constituency," he said.

"I now understand that the minister has referred himself to the first minister to inquire into the suggestion that he has broken the ministerial code.

"Can the first minister tell us whether he has completed that inquiry and what his conclusions were?

"If not when will that work be done because people need to know that there is full transparency in the way that funds are spent on bus services?"

Funds must be spent in an "entirely fair and equitable" way "in all parts of Wales", he added.

Welsh Labour leader Mr Drakeford replied: "This has been referred to me under the Ministerial Code.

"I will conclude my investigations in the normal way and the member will be better off waiting to see the results of that."