United's new number seven, Shania Hayles, opened the scoring after 20 minutes with a calm low finish, before Kosovare Asllani equalised five minutes before half time.
Both sides squandered chances in the first half and struggled to break each other down in the second 45 minutes.
Hayles almost opened her Newcastle account after just 15 minutes when Lia Cataldo broke into the box to tee her up, but she saw both efforts deflected.
United struck first when their early pressure paid off after 20 minutes when Hayles slipped the ball past Emily Orman from close range.
Jasmine McQuade won the ball inside the hosts' half before threading through Hayles, who slotted into the bottom corner.
Despite going behind, the hosts looked to play on the front foot a lot more and turned defence into attack in a flash, but a low cross to Lotta Lindstrom only found the far post.
The home side caught United on the transition minutes before half time with a swift counter-attack which allowed Asllani to calmly fire past Claudia Moan.
Newcastle almost restored their lead within a matter of minutes when a loose corner ball fell to Hayles at the back post but she couldn't direct the ball goalbound from inside the six-yard box.
It was a tactical second half which saw both teams not take as many risks, leaving the respective goalkeepers rather quiet.
The hosts looked set to take the lead for the first time when Isobel Goodwin pounced on a back pass and evaded the on-rushing Moan, only for Charlotte Potts to make a last-ditch block with the goal gaping.
It was London City who posed the biggest threat as the game entered the final 15 minutes with substitute Goodwin firing hard and low, but was straight at Moan.
Newcastle United Women: Claudia Moan, Lia Cataldo (Lois Joel 68), Deanna Cooper, Charlotte Potts, Demi Stokes, Katie Barker, Elysia Boddy, Rachel Furness (Amber-Keegan Stobbs 45), Shannia Hayles (Sophie Haywood 62), Jasmine McQaude (Isabella Sibley 68), Amy Andrews (Beth Lumsden 85)
Subs not used: Hannah Hawkins, Liv Watt, Hannah Greenwood, Georgia Gibson
