Image caption Alun Cairns has been Welsh secretary since March 2016

The chair of an assembly committee has said its members are frustrated that they have been unable to get the Welsh secretary to appear before them.

Finance Committee chairman Simon Thomas said they needed to discuss with Alun Cairns "matters essential to the governance and performance of Wales".

The committee said it had suggested possible times since May 2016, after Mr Cairns's appointed in March that year.

The UK government said Welsh ministers were better placed to give evidence.

The Finance Committee said if had given Mr Cairns the options of appearing using by video conference or Skype if that was more convenient.

Mr Thomas, Plaid Cymru AM for Mid and West Wales, said in a statement that the committee was "frustrated and disappointed at the continuing reticence" of the secretary of state for Wales "to appear before us on matters essential to the governance and performance of Wales".

"Thorough scrutiny and accountability are critical parts of any minister's portfolio, regardless of the institution in which they sit," Mr Thomas said.

He said the Finance Committee was "considering matters which will affect every person in Wales", including the devolution of tax-raising powers later this year.

Mr Thomas said Mr Cairns was legally obliged to report on the Wales Act 2014, which transfers those tax powers, but he "will not attend committee to discuss these annual reports".

"It is critical such processes are rigorously examined and that all parties involved subject themselves to such scrutiny," Mr Thomas added.

Image caption Simon Thomas says it is critical that Alun Cairns should appear

A Wales Office spokesperson said: "The Secretary of State for Wales is always happy to engage with the National Assembly for Wales on appropriate areas of policy.

"The primary focus of the National Assembly's Finance Committee is to scrutinise devolved areas where Welsh Government ministers are more appropriately placed to give evidence.

"The Welsh Affairs Committee and the Welsh Grand Committee [at Westminster] regularly scrutinise reserved areas of policy that apply to Wales and the Secretary of State for Wales appears regularly before both Committees."

The Welsh Grand Committee meets occasionally to discuss issues relevant to Wales, and includes the 40 Welsh MPs.

It has not met since 3 February 2016, six weeks before Mr Cairns became Welsh secretary, according to the UK Parliament website, but is expected to convene in the next few weeks.