Saracens say Mako Vunipola could play against Leicester at the weekend, despite being stood down by England over coronavirus fears.
Vunipola returned to England from Tonga via Hong Kong but Saracens say he has shown no symptoms of coronavirus and is not self-isolating.
An RFU spokesperson said Vunipola was "not sick" but was not in camp "on medical grounds".
However, Saracens feel Vunipola, along with brother Billy, are both safe to return to the club's training base.
A Saracens statement read: "Billy Vunipola and Mako Vunipola returned to Saracens after visiting family in Tonga which included a short stop at Hong Kong Airport.
"Travellers returning from Hong Kong are not currently subject to mandatory quarantine or self-isolation unless they become symptomatic.
"Neither Billy or Mako have displayed symptoms of the Coronavirus (Covid-19) and on their return to London were assessed by the club's medical staff.
"The duo have been around the Saracens environment for the past couple of days, with the latter available for selection this weekend.
"Saracens will continue to follow the Public Health England and World Health Organisation regulations surrounding coronavirus and the medical staff will be closely monitoring Billy and Mako on a regular basis."
Ireland's game against Italy, due to be played on March 7th, is the only Six Nations game to be postponed because of the coronavirus so far.
However, tournament organisers said on Monday that the rest of the weekend's fixtures were set to go ahead.
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