The Magpies travel to the Etihad Stadium on Sunday afternoon (kick-off 4.30pm BST) to face Pep Guardiola's title challengers, who are currently unbeaten in their previous eight league fixtures.
After suffering a 1-0 home defeat against Liverpool - United's first defeat in five matches - Howe expressed his delight in the England international pair's return to full training whilst revealing the extent of Fabian Schär's injury after the Swiss defender limped off against the Reds.
“Callum has trained all week and I’ve been really pleased with him," Howe said. "He’s trained very well and come through two very tough days. Physically, he looks good and has put a lot of work in to get to this point so I’m very pleased with the attitude, as always, with Callum. He looks in a good place and there’s a good chance he’ll be involved.
“Kieran is slightly behind him this week in the sense he hasn’t trained everyday. When he has, he trained very well so we’ll make a late decision on him. It’s incredible to have players of that quality come back into your squad. We’ve missed them not just as players but as personalities.
"I think everyone saw the impact Kieran had on the team in a very short period of time, not just with his performances but his leadership skills and the ability to help players on the pitch during games. To be able to add that back into the training group has been a brilliant lift for everybody.
“I’ve tried to stay in regular contact with both players. I think they’ve both reacted very well to the difficult situation they’ve been in, especially Callum because I think his injury was at a difficult time for him in the season. He’s very strong, resilient and he’s come back with a bounce.
“We haven’t seen Fabian this week so we hope he will be back to be available. He got a knock on the top of his foot so he went for a scan immediately after the (Liverpool) game to check it wasn’t broken as it swelled up. Fortunately, there was no fracture."
After City's crushing exit in the Champions League semi-finals on Wednesday, suffering an extra-time defeat against Real Madrid, the five-time Premier League champions shift their full attention to attempt lifting a sixth title in the space of a decade.
Howe is not allowing the Citizens' midweek loss to affect his own team and is hopeful Newcastle, currently occupying tenth place, can learn from Saturday's defeat against Liverpool in their bid to end six successive losses at the Etihad.
“It can work both ways," the 44-year-old added. "You can be emotionally affected for the positive or negative. From our perspective, we will 100 per cent prepare for the best Manchester City and we have to be the best Newcastle we can be.
“I don’t think there’s any doubt their head will be in the game. They know now they’re fighting and their focus changes to the Premier League.
"They’ve been very consistent in their results and nothing has wavered their focus. I don’t expect this to. The only thing we can control is turning up and being the best us.
“Looking back to last week, that was the disappointment for me that we just lacked a bit of intensity in our work that we’ve had consistently for the last two to three months, hence why we didn’t get the result we wanted.
“If we can add that part to our game back, hopefully we can give a good performance."
After Paul Dummett agreed a one-year extension with the club on Thursday, Howe was pleased to see the Geordie defender, who has made over 200 appearances for his boyhood club since 2013, commit his future for a further 12 months.
“He’s a great personality, Newcastle through and through," he added. "He loves the club and loves everything connected with the club. I think it’s very important that the characters that the squad have are of the highest quality and I think Paul is.
“I still think he has a lot to offer on the pitch. I’ve been really pleased to see him stay fit for a sustained period of time.
"He’s trained really well and you have to remember back to the Leeds game, which was a pivotal game for us this season, and a moment where he went into a very difficult situation, I think he played with very minimal training time that day and I thought he was outstanding against a very difficult opponent.
"He’s played his part in our success and I’m delighted he is staying."
