Isak has missed each of the Magpies' last three games since being withdrawn in the 3-1 victory at Aston Villa last month with a groin problem.
Willock, meanwhile, has been troubled with injuries throughout this season and has been reduced to only 301 minutes across six appearances in all competitions.
The former Arsenal midfielder was sidelined with a hamstring injury at the beginning of the campaign and he is now towards the end of his recovery from an Achilles problem which has kept him out since mid-November.
Howe has confirmed that both players have taken part in training this week and the Newcastle duo will be assessed ahead of Saturday's trip to North London.
«They have trained this week – it has been good to see them back on the grass,» Howe told reporters at a press conference on Friday.
«It has been a long time for Joe but he is a huge player for us. It's been great to see him back among the group — he is a very popular member of the squad. I'm really pleased for him this week.
»With Alex, again, he's a really important player. He's trained really well, so we're happy with both players.
«We'll have to wait and see — we've one more training session – but we've been pleased with their progress.»
Fabian Schar has also trained this week and the defender is in contention to face the Gunners despite leaving the pitch clutching his arm after Newcastle's 2-2 draw with Bournemouth at St James' Park last weekend.
However, Callum Wilson (pectoral), Nick Pope (shoulder), Matt Targett, Joelinton (both
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