The phrase "assurance of support" is correct and usable in written English.
It can be used when expressing a guarantee or promise of assistance or backing in a particular context.
Example: "The organization provided an assurance of support to all its members during the transition period."
Alternatives: "guarantee of assistance" or "commitment to support".
But before he was prepared to commit himself to any Protestant league and undertake a military campaign in Germany, Gustav required adequate assurance of support.
"There is a broader message to you all, which is the government's intrinsic belief in academies, that opening an academy is just the start of a tough journey of improvement, and our assurance of support if things go wrong.
Moreover, this assurance of support in populous Essex County could prove to be significant in a statewide primary since it has provided the margin of victory in past contests.
After getting burned by Trump in December on a spending bill the Senate passed and the president disavowed, McConnell wanted to move as fast as possible to a vote following Trump's assurance of support.
Without the assurance of support to provide basic necessities to a child, many such caregivers cannot take on the responsibilities of a legal guardian and as a result many children remain in foster care longer than they should.
Some British news media analysts suggested that the fact that Mr. Murdoch's remarks had been recorded and leaked — potentially turning tabloid eavesdropping tactics against the tycoon himself — showed that not all of the Sun journalists attending the March meeting had been satisfied by his assurance of support.
Israel is seeking assurances of support from the US, should it decide to launch air strikes against Iran's nuclear facilities.
Theoretically it needs no assurances of support from crossbenchers and should be able to pass legislation through the House of Representatives – as long as nothing goes wrong.
The Bush administration, with its broad assurances of support for Georgia, has come in for strong criticism in Georgia for having emboldened Mr. Saakashvili to challenge Russia.
But Mr. O'Neill offered no such assurances of support for Argentina, which the Bush administration views as having mishandled its economy.
