Stephen Crabb's first day as Welsh secretary
Welsh secretary Stephen Crabb started his new role discussing the impact of plans set out in the Queen's Speech at the Welsh grand committee.
He told BBC Radio Wales the electrification of the Valleys lines was a top priority but said the current row over funding must be put aside.
He also backed David Cameron's attacks on the Welsh NHS, claiming Wales "shouldn't settle for second best".
Mr Crabb replaced David Jones who was sacked during the cabinet reshuffle.
Grand Committees give MPs the opportunity to debate issues affecting their region.
On Wednesday the debate focused on the impact of the Wales Bill, currently progressing through parliament, which would give the Welsh government some taxation and borrowing powers.
Speaking to BBC Radio Wales about his new appointment Mr Crabb said he no longer supported claims he made seven years ago that the role of Welsh Secretary was meaningless.Ambitious Wales
He said the post had been reinvigorated by the prime minister in recent years and David Cameron had told him he wanted him to "get stuck in" and speak up for Wales.
Talking about what he plans to do in his new post, the Preseli Pembrokeshire MP said he was focused on pushing forward with the upgrade of the Valleys rail line in south Wales.
He said the "knotty difficulties" surrounding who pays for it were still up for discussion and he wants to meet colleagues in Westminster and the Welsh government to try and reach a "common goal".
The Tory MP also spoke about a "battle for a better public services in Wales" and said politicians should not shy away from holding public services to account.
He said: "Across a number of very important criteria public services in Wales are not delivering as best as it can be, and I think we should be ambitious for Wales and we shouldn't settle for second best".
"I think when David Cameron stands up at the dispatch box and says we are ambitious for Wales, we think the people of Wales deserve a lot better, I think he should be commended that we're shining a spotlight of scrutiny into that and we shouldn't shy away from the political arguments around that."