A pitch invader gatecrashed the Portugal vs Uruguay game on Monday evening whilst carrying a Pride Flag and a politically focussed t-shirt.

The clash between the two favourites in Group H proved the standout offering at the World Cup on Monday.

Millions of viewers tuned in worldwide to watch the headliner, which would see global icon Cristiano Ronaldo face off against the likes of Liverpool legend Luis Suarez and current star Darwin Nunez.

As a result of the high-profile nature of the game, one protester clearly identified it as a prime opportunity to raise awareness for his chosen political issues.

The criticism of this year's World Cup has been widespread and so it probably wasn't too much of a surprise for fans when, in the second half, the man burst onto the pitch in an act of protest.

He carried with him a Pride Flag in support of the LGBTQ community.

His t-shirt also had 'Save Ukraine' across the front, whilst the back read 'Respect For Iranian Women'.

View the moment below.

WATCH: Pitch invader in Portugal vs Uruguay

The political issues facing the Qatar World Cup

FIFA have come under heavy fire for allowing football's most prestigious competition to take place in Qatar.

The nation has widely differing opinions and beliefs to much of the western world, resulting in a very different treatment of women, workers and across various other areas of general life to what much of the footballing world are accustomed to.

Only last week, the Football Associations of several European nations hit out at FIFA after the governing body opted to ban the use of the 'One Love' armbands that many captains were due to sport in games at Qatar.

READ MORE: One Love armbands: Statement released as Qatar World Cup initiative is scrapped

Whereas the war in Ukraine and the high-profile mass protests in the nation of Iran represent two other very relevant political issues that many feel the tournament is obliged to address.

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