The UK government said that as health is a devolved matter, only a restored Stormont executive could take decisions on the health service.
But added that Northern Ireland Secretary Julian Smith is "very concerned about the situation in the health service".
In a statement, the Northern Ireland Office said that while Mr Smith had further discussions with the NI Civil Service on Tuesday, he "has no powers to direct them or take decisions on health matters".
"We cannot comment on the possible actions of a future government."
Two more days of industrial action, short of strike action, are to be held on 10 and 11 December.
Members of the RCN and trade unions Unite, Unison and NIPSA have voted to strike on 18 December.
Stephen spoke to NI Chief Medical Officer Michael McBride.