Wheat and soybeans also gained, supported by US President Donald Trump saying that a trade deal with China could happen quickly.
The most-active corn contract on the Chicago Board of Trade was up 1pc
at $3.93-1/2 a bushel by 0946 GMT, trading near a one-year high of $3.99 struck earlier in the week.
Corn prices rallied in the past week as persistent rain threatened to prevent farmers from planting some corn acreage. More heavy rain is forecast in the western Corn Belt next week after showers this week exacerbated soggy conditions this spring.
But the Trump administration's announcement on Thursday of a $16 billion farm aid package to offset losses from the trade dispute with China pushed corn futures lower in the last session.
The package, the bulk of which will be spent on direct payments, surprised growers and traders because it did not include separate payment rates for crops, contrary to expectations that it would favour soybeans over corn.
"It's a calculation that US farmers are going to have to make to see if it's worth planting," said Nathan Cordier of crop consultancy Agritel.
"It's too soon to be able to draw any conclusions."
Soybeans were up 0.3pc at $8.23-3/4 a bushel.
The most valuable US farm export to China before the trade row, soybeans had been expected to be a priority in the US aid programme, potentially prompting farmers to shift acreage from corn to soy.
"The USDA's intention to make aid to US farmers crop-neutral is a plus for beans," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia.
Remarks by Trump on Thursday, in which he predicted a swift end to the trade war with China, also lent some support to soybeans and wider markets after a period of increased tension in discussions between Washington and Beijing.
Wheat was up 0.6pc at $4.73 a bushel, with markets capped by favourable harvest prospects across Europe.