Ulster will host Leinster in a United Rugby Championship interpro on the same day that Ireland face England at Twickenham.
The URC this afternoon confirmed the new kick-off details of Ulster's two derby matches that were postponed over the Christmas period, following their Covid-19 outbreak.
Their meeting with Connacht at Kingspan Stadium, which had been due to take place on St Stephen's Day, will now be played on the eve of the Six Nations Championship; Friday 4 February, with an 8.15pm kickoff.
Dan McFarland's side also saw their New Year's Day clash with Leinster rescheduled, with the URC confirming it will now be held on Saturday 12 March in Belfast, with a 7.35pm kick-off.
That falls on the same day that Ireland take on England in the Six Nations, with their Test match getting under way at 4.45pm.
The new arrangements mean the derby games will take place without Ireland's international players.
The URC are yet to reveal details on when the remaining postponed interpro will take place, with Munster's Thomond Park derby against Leinster also expected to be played on a Six Nations weekend.
Follow Bath v Leinster (Saturday, 1pm), Ulster v Clermont (Saturday, 5.30pm), Stade v Connacht (Sunday, 1pm) and Munster v Wasps (Sunday, 3.15pm) via our live blogs on rte.ie/sport or on the RTÉ News App, or listen to live radio coverage of Bath v Leinster on RTÉ Radio 1 Extra and RTÉ Radio 1.