Shadow foreign secretary Douglas Alexander has said Prime Minister David Cameron must "urgently consider reversing his decision" to attend the Commonwealth Heads of Government summit in Sri Lanka this week.
"For months Labour has urged the Government to do more to raise Britain's concern over human rights in Sri Lanka in the run up to the summit," Mr Alexander said.
"If the Prime Minister now chose to reverse his decision to attend the summit - even at this late stage - he would have Labour's full support."
The political fallout from last week's Syria vote has continued with a Cabinet minister saying the results would be a matter for Ed Miliband's conscience and the shadow foreign secretary admitting he was not comfortable with the position Labour now finds itself in.
Speaking on BBC Breakfast Shadow foreign secretary Douglas Alexander said:
The right response is not simply to say something must be done, however loudly. It is to both ask and answer the question 'What steps can be taken to make a horrendous situation better?'
Now, as the Labour Party, we have never in principle ruled out the use of force in Syria. But we haven't yet heard from the Government what its strategic objective would be for any military action.
Would it be to degrade and diminish the capability of Assad to use chemical weapons? Would it be an attempt to try and change the course of a highly complex, intractable civil war?
We simply haven't had those questions answered.
And that's why I do think the Prime Minister should bring Parliament back so that they can offer their case both to politicians and to the people before any decision is taken to commit British forces into combat.
The shadow foreign secretary said the leaks that suggest the GCHQ had tapped data cables "underlines the need" for ministerial oversight of intelligence agencies.
Douglas Alexander said: "The latest reports in the Guardian underline the need for effective parliamentary and ministerial oversight of GCHQ and our other intelligence agencies.
"Whilst GCHQ do vital work to keep us all safe from harm, it is also vital that they do so with the legal framework set down by Parliament, and with proper safeguards in place to protect people's privacy.
"We urged the Intelligence and Security Committee (ISC) to look into these issues raised by the Guardian, and their work is now under way.
"These latest reports reinforce the urgency and importance of the ISC's work on this issue."
Labour’s Shadow Foreign Secretary Douglas Alexander has said there is unease "across party lines" about the Prime Minister's comments on the potential supply of British arms to Syria's opposition forces. In a statement, he said:
For months Labour has called on the Government to answer basic questions about their approach, such as how would the Prime Minister ensure that weapons supplied did not fall into the wrong hands and how would this step help to de-escalate the conflict rather than prolong it?
The G8 is a key window of opportunity for David Cameron to exert pressure on President Putin and it is vital that he uses the coming hours to do so.
Labour's Shadow Foreign Secretary Douglas Alexander has accused David Cameron of losing control of his party over Europe.
It follows reports that the Conservatives are considering publishing a draft bill which would guarantee a referendum on Britain's membership of the EU.
"This seems to be just the latest panicked response from the Prime Minister who is now following, rather than leading his backbenchers" Mr Alexander said.
"David Cameron is a Prime Minister who has both lost control of the agenda and lost control of his party."
"Labour have said that we don't think committing now to an in/out referendum up to four years from now is in the national interest because the priority must be getting growth into the economy not getting Britain out of Europe."
This seems to be just the latest panicked response from the Prime Minister who is now following, rather than leading his backbenchers.
David Cameron is a Prime Minister who has both lost control of the agenda and lost control of his Party.
Labour have said that we don't think committing now to an in/out referendum up to four years from now is in the national interest because the priority must be getting growth into the economy not getting Britain out of Europe.
This latest step has more to do with trying to get his Party back in line rather than getting the economy back on track.
Labour's Shadow Foreign Secretary Douglas Alexander has said that the Prime Minister's comments on the EU, made on the BBC's Today programme, raise more questions than they answer:
The gap between his back benchers and our EU partners remains un-bridgeable.
It is little wonder that British business leaders like Richard Branson and Martin Sorrell, together with the Americans, the Germans and the Austrians, have all warned in the last week of the dangers of the UK sleepwalking towards exit from Europe.
At a time when the priority should be jobs and growth, the Prime Minister sadly seems willing to put vital UK investment at risk for the sake of trying to keep his party united.