The supermodel siblings have been inspired by fellow catwalk beauty Mica Arganaraz, 29, who called on her colleagues in the industry to pledge the money they make from the shows to organisations offering assistance to the people of the war-torn country.
Bella, 25, wrote on Instagram: "To watch my Ukrainian friends and colleagues working hard here in Europe, so close but so far from their families/friends/homes in Ukraine who are experiencing one of many brutal occupations and invasions happening right now in the world is a very emotional and humbling experience for me.
"We rarely have control of our work schedules, and this week has really shown me the strength and perseverance of the people around me who are going through pure terror.
"To hear their stories and emotions first-hand is devastating and I wholeheartedly stand with them in support. I stand alongside every person that has been affected by this war and the innocent people whoâs lives have been changed forever from the hands of 'power' (sic)."
She then confirmed she would be donating her fees.
She added: "Taking after Mica and My amazing Sis, I will be donating all of my earnings from this Fashion Week directly to organizations that are providing help, refuge and medical aid to those in need on the ground in Ukraine, as well as continuing to support our Palestinian people and land (sic)."
Bella had already shown her support for Mica's donation initiative.
She said: âYou said it @micaarganaraz.
âWe have many Ukrainian friends, colleagues, models, production, casting and to see the lack of communication/knowledge about a war...so close is very very sad. Itâs incredibly odd to be walking in fashion shows as our work, especially during a time like this.
âI compel the people of our industry to do their research and have open conversations about the hell that is happening next door.â
Gigi - whose father, Mohamed, is an Arab Palestinian - previously confirmed she is donating all of her earnings for Fashion Week to Ukraine and Palestine.
She wrote on Instagram: âHaving a set Fashion Month schedule has meant that my colleagues and I often present new fashion collections during heartbreaking and traumatic times in history. We donât have control over most of our work schedules, but we would like to walk âforâ something.
âFollowing in the footsteps of my friend @micarganaraz, I am pledging to donate my earnings from the Fall 2022 shows to aid those suffering from the war in Ukraine, as well as continuing to support those experiencing the same in Palestine. Our eyes and hearts must be open to all human injustice."
In February, Mica announced: âI have to say it feels very weird walking fashion shows knowing thereâs a war happening in the same continent.
âI will be donating part of my earnings of this fashion week to help Ukrainian organisations."
She urged: "To my model friends and colleagues and whoever is also struggling with this feeling, perhaps this is something we could all contribute to."