The phrase "allegedly supported" is correct and usable in written English.
It can be used when discussing claims or assertions that are reported to be true but have not been definitively proven.
Example: "The report stated that the project was allegedly supported by several influential organizations."
Alternatives: "reportedly backed" or "purportedly endorsed".
In the Lebanese port city of Sidon in 2013, Assir's supporters battled the Lebanese army, allegedly supported by Hezbollah, from their fortified complex of apartment buildings, which included the Bilal bin Rabah Mosque, where Assir preached and often met with the media.
Aerial attacks, allegedly supported by unmanned American drones, on training camps and AQAP positions in the south of the country were followed by a ground campaign.
Today there was a bomb blast at the American Embassy in Kabul for which the Haqani network allegedly supported by the Pak military has been blamed.
The groups they allegedly supported were the armed Basque separatist group Eta, the Catalan separatists Terra Lliure and the far-left October First Anti-Fascist Resistance Group (Grapo).
On Saturday, a new campaign was launched – the People's Pledge – to bring about an In/Out referendum on British membership of the European Union, allegedly supported by activists on both sides of the argument (the Lib Dems cunning plan before last May's election) but mostly europhobic.
In the civil war of 1994, Saudi Arabia allegedly supported the Southerners as they tried, unsuccessfully, to break away from the North.
He cemented his pariah status by allegedly supporting the Ayatollah Ruhollah Khomeini's death sentence against the author Salman Rushdie in 1989; supporters of free speech burned Cat Stevens albums after his views, which he says were misinterpreted, became public.
In 2009, the U.N. placed sanctions on Eritrea, for allegedly supporting al-Shabaab in order to undermine Ethiopia.
And it has treated civilian employees of Hamas — including police officers, judges, clerks, journalists and others — as combatants because they allegedly support a "terrorist infrastructure".
A firebrand Islamist preacher who was banned from the UK after praising al-Qa'ida attacks on the West has been arrested in Lebanon for allegedly supporting terrorism.
Bauer argues that a judge should reject Cruise's motion, citing statements from confidential sources that allegedly support their magazines' claims.
