Both sets of fans will join together in a minute's applause in memory of supporter Lily Harris, 33, who passed away on 5 November after a long battle with cystic fibrosis.
A number of Hammers fans gathered on social media in order to spread the word about holding a remembrance in the 33rd minute during their next home game, which takes place against Spurs on Saturday lunchtime at the London Stadium.
Her family and fiancee Chris have appealed for support on Twitter to raise awareness following Lily's death and have received a huge response from fans of both clubs.
"Please applaud in the 33rd minute of the @WestHam game this Saturday in memory of my sister @lilyfharris who unfortunately passed away on the 5th Nov," the tweet read.
<blockquote class="twitter-tweet" data-lang="en-gb"> <p dir="ltr" lang="en">So touched that <a rel="nofollow" target="_blank" href="https://twitter.com/WestHam?ref_src=twsrc%5Etfw" class="body-link" data-vars-item-name="BL-4294356-https://twitter.com/WestHam?ref_src=twsrc%5Etfw" data-vars-event-id="c23">@WestHam</a> fans are planning a minute’s applause in the 33rd minute of the Spurs game as a tribute to my gorgeous fiancée <a rel="nofollow" target="_blank" href="https://twitter.com/lilyfharris?ref_src=twsrc%5Etfw" class="body-link" data-vars-item-name="BL-4294356-https://twitter.com/lilyfharris?ref_src=twsrc%5Etfw" data-vars-event-id="c23">@lilyfharris</a> who died earlier this month. Thanks to <a rel="nofollow" target="_blank" href="https://twitter.com/Baz1980WHU?ref_src=twsrc%5Etfw" class="body-link" data-vars-item-name="BL-4294356-https://twitter.com/Baz1980WHU?ref_src=twsrc%5Etfw" data-vars-event-id="c23">@Baz1980WHU</a> <a rel="nofollow" target="_blank" href="https://twitter.com/mark_messingham?ref_src=twsrc%5Etfw" class="body-link" data-vars-item-name="BL-4294356-https://twitter.com/mark_messingham?ref_src=twsrc%5Etfw" data-vars-event-id="c23">@mark_messingham</a> & <a rel="nofollow" target="_blank" href="https://twitter.com/ExWHUemployee?ref_src=twsrc%5Etfw" class="body-link" data-vars-item-name="BL-4294356-https://twitter.com/ExWHUemployee?ref_src=twsrc%5Etfw" data-vars-event-id="c23">@ExWHUemployee</a> for making it possible. Lily would love it ❤️ <a rel="nofollow" target="_blank" href="https://t.co/mHIwo7DGKa" class="body-link" data-vars-item-name="BL-4294356-https://t.co/mHIwo7DGKa" data-vars-event-id="c23">pic.twitter.com/mHIwo7DGKa</a> — Chris Westwood (@chrisjwestwood) <a rel="nofollow" target="_blank" href="https://twitter.com/chrisjwestwood/status/1197097148720001024?ref_src=twsrc%5Etfw" class="body-link" data-vars-item-name="BL-4294356-https://twitter.com/chrisjwestwood/status/1197097148720001024?ref_src=twsrc%5Etfw" data-vars-event-id="c23">20 November 2019</a>
After learning of the campaign, the Tottenham Hotspur Supporters' Trust offered their participation and shared a tweet notifying Spurs fans of the arrangement.
"If you’re at the London Stadium tomorrow and there’s applause in the 33rd minute, it’s for Lily.
"Please join in and tell the person next to you to join in, too."
The two sides go head-to-head in the first match back after the international break in what will be Jose Mourinho's first game in the Tottenham dugout.
