"reject demands" is correct and usable in written English.
You can use it when you are refusing to comply with an ultimatum, or when you are disagreeing with a request. For example: "The management team has decided to reject the union's demands for higher wages."
ExxonMobil is urging shareholders to reject demands that it move into renewable energy.
France and Germany gained enough backing to reject demands from the European Commission for additional savings in 2004, saying that would endanger the economic recovery.
But the warnings drew an immediate riposte from the cleric, Moktada al-Sadr, who emerged from days of silence to reject demands for the militiamen to surrender.
Meanwhile, Deputy Prime Minister Nick Clegg has continued to reject demands he resign as the leader of the Liberal Democrats, a position which has been bolstered by potential successor Vince Cable's insistence that "there is no leadership issue".
Well-meaning critics repeatedly pointed out that the euro had a rigid set of institutions with their own internal logic that would simply reject demands to abandon austerity and write off debt.
JERUSALEM — The discord between the United States and Israel over Jewish building in East Jerusalem deepened Tuesday with Israeli officials saying they would reject demands by Washington and expressing anger over the public upbraiding of Prime Minister Benjamin Netanyahu by the Obama administration.
He has rejected demands for a new Duma election.
Feb. 22, 2011: Gaddafi rejects demands that he relinquish power.
Domestically, he rejected demands for democratization and suppressed opposition.
Despite that, Mr Corbyn rejected demands for him to sack Mr Livingstone from his defence role.
Georgia rejects demands that Russian troops be allowed into the gorge.
