A special meeting of the Assembly will be held to address issues surrounding the Renewable Heating Incentive scandal.
The first and deputy first ministers have asked the assembly speaker to “convene a special sitting” next week.
The government-led energy initiative was meant to encourage businesses to switch to eco-friendly wood burning boilers.
But it paid out more in subsidies than the fuel cost, meaning users could abuse the system to earn more money by burning more fuel. It closed in November 2015, with a massive overspend of £400m.
In a joint statement, Mrs Foster and Mr McGuinness said they wanted MLAs to return to Stormont to discuss the RHI issue.
The Executive Office statement added: “This will facilitate a full statement to be made by the First Minister to Members on the matters of public concern relating to RHI.
“RHI was discussed by the Executive today and ministers around the table underlined the seriousness of the issues involved and the importance of restoring public confidence.
“It was also emphasised that detailed plans are being finalised to significantly reduce the projected losses in the years ahead.”