Media playback is unsupported on your device Media caption UUP leader Mike Nesbitt announced that his party will form an opposition at Stormont.

The leader of the Ulster Unionist Party (UUP) Mike Nesbitt, has announced that his party will go into opposition at Stormont.

He told the new assembly at its first sitting that the move "heralds a new era for devolved politics at Stormont".

Mr Nesbitt added: "Let battle commence."

SDLP leader Colum Eastwood said his party has not decided yet whether it would go into opposition or government.

Earlier, Mr Nesbitt said his party's decision was a "big, bold step forward to normal democracy".

The UUP's 16 assembly members unanimously agreed on the decision to enter opposition.

He said: "We had two tests which would determine whether we went back into the executive.

"The first was whether it was a progressive programme, and it's clear we won't have the answer for that perhaps until the end of the year.

Image caption Colum Eastwood said the SDLP were focused on the negotiations

"The second test was whether the DUP and Sinn Féin were going to allow a sort of collective spirit in terms of delivery.

"And in our short discussions over the last two days, it's very clear the DUP and Sinn Féin are going to retain ownership of the programme for government and what's going to be published is motherhood and apple pie.

"We're not really interested in discussing what type of apples go in the pie. Our concerns run a lot deeper than that.

"So, both tests have been failed. We add in the fact that the chief constable says that nothing has changed in terms of the security situations since last October.

"So, on that basis, we're out."

Focus

Mr Nesbitt added that opposition would be stronger and there would be a "more honest" executive if the SDLP and Alliance Party joined the UUP in opposition.

He said that he had not talked with the SDLP yet but "would welcome a discussion with Colum at this point".

Mr Eastwood said his party would decide on whether to go into opposition until after talks over a programme for government had finished.

"We're not focused on big announcements. We're focused on working hard to get a programme of government we can sign up to," he said.

Image caption Martin McGuinness said he was 'deeply disappointed' at the UUP's decision

"There's been many negotiations over the last number of years and we've always stuck in to the end.

"We wait until all the negotiation is done and then make a decision. That's the right way to do a negotiation."

He added: "We have a job to do, because now we're the only party holding the DUP and Sinn Féin's feet to the fire to achieve a proper progressive programme for government."

Alliance party leader David Ford congratulated Mr Nesbitt on the "soundbite of the day".

'Lack of leadership'

"Some of us recognise that government is a bit more substantial than the soundbite of the day" he said.

Martin McGuinness said he was "deeply disappointed" that the UUP had decided to go into opposition.

"I do think that rather than it be seen as leadership, it will be seen as a lack of leadership," he said.

"It will be seen as a lack of the Ulster Unionist Party's ability to accept the democratically expressed wishes of the people who have charged the DUP and Sinn Féin to lead this administration forward."

He added: "We now wait with considerable interest to see if the SDLP are going to stand by the principles of the Good Friday Agreement."