The former foreign secretary William Hague has said that the UK should not rule out having some of its own forces on the ground in Syria and Iraq if it is to defeat Isis.

Writing in the Telegraph, Hague argues that the destruction of Isis would require a military presence on the ground “where state failure has allowed a terrorist organisation to roam free”.

“That [military presence] should be Syrians, Iraqis or other Arabs, but it would be a mistake for Britain or other western nations to rule out some of our own forces operating there if that can make the crucial difference to the outcome,” he writes.

On Thursday David Cameron will present his plan for tackling Isis to parliament, before deciding whether to put the issue of launching airstrikes on Isis in Syria to a vote by MPs. The aim of the airstrikes would be to dislodge Islamic State from its stronghold in Raqqa and so eradicate its training grounds.

Hague, who was foreign secretary between 2010 and 2014, writes that the publication of the long-awaited Chilcot report into the war in Iraq will be “a time to acknowledge that we were wrong about the invasion of Iraq”.

“We relied too much on evidence that turned out to be flimsy, and let our most important ally, the United States, become exhausted when there were many other battles to fight,” he writes.

But, he says, “the contrasting lessons of [the Rwandan genocide, where the international community didn’t intervene] and Iraq should show all of us that there is no simple, binary choice about being pro- or anti-intervention overseas.”

Hague writes that the memorial to the Rwandan genocide in Kigali should be visited by “every pacifist, every ‘stop the war’ fanatic, every leader of the opposition who struggles with the concept of using the military at all, for it teaches us that there are circumstances where standing aside is incompatible with basic humanity, morality and mercy”.

Jeremy Corbyn, the Labour leader, is thought to remain opposed to action in Syria, but has told his shadow cabinet that he wants it to come to a collective view. Labour’s position on extending airstrikes across the border with Iraq to Syria is crucial as Cameron cannot afford to be defeated as he was in 2013 in a parallel vote.

Labour’s leadership says it is broadly in agreement with the conclusion reached by the Commons foreign affairs select committee, which reported that the government had not yet set out a coherent strategy on tackling Isis in Syria. The party is awaiting Cameron’s response to the committee’s report on Thursday before it decides its position.

Around 15 Labour MPs are likely to vote in favour of airstrikes regardless of the party’s official position and many more could join them. It is likely Cameron will decide as early as Monday on the advice of government whips whether to put the issue to a Commons vote next week.

Hague also suggests that it may be right to consider partitioning Syria and Iraq. “The borders of Syria and Iraq were largely drawn by two British and French diplomats in 1916,” he writes. “They should not be considered immutable.

“If the leaders of either country cannot construct a state where all communities can live together, it will be right to consider international support for their partition. Kurds have shown their ability to run their own affairs. A subdivided Syria might now be the only one that can be at peace.”