The US Senate Committee on Foreign Relations has held a confirmation hearing for the new US Ambassador to Ireland.

US President Barack Obama nominated Missouri-based Irish-American lawyer Kevin O'Malley at the beginning of June.

Democratic Senator Claire McCaskill introduced Mr O'Malley to the committee this afternoon, describing him as "smart, loyal and hard-working", who had Irish grandparents on both sides of his family.

She said he had held dual Irish-US citizenship until recently when he gave up his Irish citizenship as part of the confirmation process for the post of ambassador.

Ms McCaskill said he loved his country and loved Ireland and would be a good choice to represent US interests in what she described as one of the US's important allies.

Democratic Senator Roy Blunt of Missouri also addressed the Committee on behalf of Mr O'Malley.

He described Mr O'Malley as someone who understands both the United States and Ireland.

He said he brought an "incredible background and a more incredible enthusiasm for the job".

Mr O'Malley said if confirmed he would participate in discussions surrounding the Irish corporate tax regime.

He was asked by Republican Senator Ron Johnson for his views on what he described as the current US political resentment for Ireland's corporate tax regime.

Mr O'Malley said he felt there were a number of compelling reasons for US firms to do business in Ireland: it was an English-speaking country, with a well-educated and dedicated workforce, in the eurozone and was strategically located at the entrance to Europe, and that the country "appreciates America and American goods".

He said that both the US and the EU were currently having discussions with Ireland about tax and that if confirmed, he would participate in those discussions.

When asked what the Obama administration's position on Ireland's tax regime was, Mr O'Malley said he did not know, but that he did not think the administration had taken a position on the tax regime of another country.

Mr O'Malley said that he would like to meet all of the parties in Northern Ireland to try to find agreement on the Haass proposals.

He said he would like to find out where the sticking points are and why the widely praised agreement had not gone through before now.

Mr O'Malley said he would urge all parties to return to the table and try to adopt agreement along the lines put forward by Richard Haass.

The committee has concluded its confirmation hearing. It will vote on Mr O'Malley's nomination at the close of business tomorrow.

If confirmed by the committee, his nomination will then go forward to the full Senate for another vote.

It is currently taking an average of 262 days for presidential nominees to be fully confirmed by the Senate.