Sinn Féin leader Gerry Adams has contended the political landscape of the North and South of Ireland has been changed forever by the emergence of his party as a permanent "major player".

In his keynote presidential address to the Sinn Féin ardfheis in Wexford Opera House tonight, Mr Adams claimed his party had permanently put an end to one party rule in the North, and that "two-and-a-half party rule" in the Republic was also on the way out.

Many of today’s political problems in Ireland, he told over 1,000 delegates, stemmed from a “toxic political culture” which has been prevalent in both States since the time of partition.

In an attack on the three largest political parties in the South, he asserted “counter-revolutionaries” came to power which were conservative in nature and copper-fastened partition.

“This toxic political culture led to the abuses of power in planning, in the banks, in church, and State-run, institutions, and in the health service.

"An elite - politically represented by the Fine Gael and Fianna Fáil leaderships, often supported by the Labour Party - oversaw a culture of corruption and golden circles.

“These are the same interests that collapsed the Irish economy six years ago.”

In an assertion of his party’s prospects ahead of the local and European elections in May, Mr Adams said Sinn Féin was now a major player in both states on the island and would be running 350 candidates in the forthcoming local and European elections.

“One party rule in the North has gone and two-and-a-half party rule in this State is going also.

“However well they regroup, Fianna Fáil will never, ever again be the dominant force they once were.”

In an Irish passage of the speech he said Sinn Féin had a message for the elites: “We are here and we are not going anywhere but forward (Tá Sinn Féin anseo agus níl muid ag dul áit ar bith, ach ar aghaidh).”

Mr Adams also called for left-leaning parties to unite and present common platforms, a call he has made already this year but which has not been taken up by any of the opposition parties so far.

“The left needs to come together around viable alternative policies and take on the conservative establishment,” he said.

While the political situation in the South dominated his speech, he said progress had been made in the talks chaired by Richard Haass in December and signalled Sinn Féin determination to resolve issues such as Acht na Gaeilge (The Irish Language Act); a Bill of Rights and the Long Kesh site.

He said issues of identity and contentious Orange Order parades would be dealt with too and said he was willing to meet with the Orange Order at any time.

“I want to see the Orange Order treating it Catholic neighbours with respect. I want to see it upholding law and order. The Orange Order of Ireland is one of our national traditions. Orange is one of our country’s national colours,” he said.

The half-hour speech, delivered to a packed auditorium, was critical of the Government on a wide range of Government policies, including property tax, water charges, health, arts and what he said were excessive wages at the top of the public sector.

He promised Sinn Féin in power would ease the tax burden on ordinary people by removing the property tax. He also said the party would unveil comprehensive plans for local government reform in the coming weeks.

The speech also contained a tribute to Nelson Mandela, who Mr Adams described as a “friend of Ireland and Sinn Féin”.

He also reiterated his party's claim to be the only "real and credible opposition in Leinster House".