A former US senator tasked by Washington to assess the state of the peace process in Northern Ireland has met politicians in Belfast.

Gary Hart, a two-time contender for the Democratic presidential nomination in the 1980s, had scheduled meetings with representatives of the main Stormont parties throughout today.

He has been asked by US secretary of state John Kerry to establish the extent of the current problems at Stormont and whether the US administration can help.

His visit came as a former senior aide to ex-president Bill Clinton, Nancy Soderberg, accused political leaders in Northern Ireland of an "abysmal abdication of leadership" and being "far too stuck in the past".

Stormont is currently hamstrung by a range of impasses, with the Democratic Unionist and Sinn Fein-led five-party mandatory coalition unable to reach consensus on numerous big ticket issues.

Eight months ago intensive talks chaired by former US diplomat Dr Richard Haass to resolve long-standing disputes around parades, flags and the toxic legacy of the Troubles ended in failure.

In July an effort to reconvene negotiations in earnest, this time chaired by a senior Stormont official, suffered a similar fate after unionists walked out as part of protest action against a partial ban on a contentious Orange Order parade.

It is highly unlikely any further all-party talks will take place before the UK government responds to a demand by unionist and loyalist parties and the Orange Order for a separate commission of inquiry to be set up into the restricted parade in north Belfast.

Mr Hart, who at this stage is not assuming as prominent a role as Dr Haass, is also meeting with representatives from the British and Irish governments on his visit across the Atlantic.

The politician, whose second bid for the Democratic nomination in 1988 ended in scandal after the married politician was pictured on a yacht with a model sitting on his lap, is keeping a low profile in Belfast and has not yet made any public statements about his meetings.

Emerging from his encounter with the US diplomat, Deputy First Martin McGuinness said: “I met with Senator Hart and briefed him on the current serious challenges facing the political process in the North.

“I made it clear that Sinn Féin welcomes continued US engagement in the political process as the US has played a positive role in the development of the Irish peace process.

“It remains our view that we can find a resolution to all the difficulties facing the political process through genuine engagement by all parties and a hands-on proactive approach by the British and Irish governments in any negotiations.”

DUP deputy leader Nigel Dodds said he was happy to meet the former senator for what he described as an "informal meeting".

“In the last 20 years Northern Ireland has made massive strides forward,” he said ahead of the encounter.

"When Gary Hart was in Congress, Belfast would have made headlines in the US for all the wrong reasons. Today Northern Ireland is the most successful region anywhere in the United Kingdom at attracting foreign direct investment. Progress has been made and despite others behaving in an irresponsible way, the DUP wants to keep Northern Ireland moving forward."

Ms Soderberg, Mr Clinton's deputy national security adviser and a former US ambassador to the United Nations, made her scathing remarks about the current Stormont situation in an article in the Irish Times reflecting on the upcoming 20th anniversary of the 1994 IRA ceasefire.

“Rather than spending these past years building a shared prosperity, both sides remain far too stuck in the past, making progress vulnerable and even reversible,” she said.

“Certainly, progress has been made, on governing, on policing and holding the peace. But the two communities remain far too focused on the injustices of the past.”

She acknowledged compromise was difficult given the pain inflicted on both sides during the conflict. “But that is where leadership comes in,” she added.

“Richard Haass, the chair of last autumn’s unsuccessful negotiations, has laid out proposals to help both parties get past their fixation on the injustices of the past, including a programme of historical investigation, information recovery, and thematic appraisals of patterns and practices by state and paramilitary forces.

“But the parties have failed to pick up that plan to deal with the past, and thus they are failing to get on with the future. That is an abysmal abdication of leadership.

“Good leaders would be able to recognise the righteousness of the other side and step forward to compromise and build a more prosperous future.

“Good leaders would get past the flags, parades and the legacy of the violence of the Troubles and work together to attract investment, technology, and build the best schools which are no longer segregated.

“So on this anniversary of peace, let the leaders of Northern Ireland think about the thousands of people walking the streets today who would have died had the ceasefire not taken hold in 1994. They want to live in the future, ideally a prosperous one. It’s time to get beyond the past and build a Northern Ireland that can compete and thrive in the 21st century.”

PA