The actress, who currently stars in Woody Allen's Vicky Cristina Barcelona, is due to marry fellow actor Ryan Reynolds.

But the 23-year-old has insisted she won't step down the aisle without having her twin brother Hunter around, who is currently working on the Democratic candidate's campaign.

A friend told the Daily Express: "Ryan has been wanting to marry Scarlett for some time and was thrilled when they got engaged in May.

"He'd marry her tomorrow if he could but Scarlett’s twin Hunter is really busy working on Barack Obama's presidential campaign.

"He's working all the time so Scarlett wants to hold off until the election is over."

Scarlett has been very open about her support of Obama's race to the White House - even sending advice to the candidate via email.

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