LONDON (Reuters) - Eight million Americans admit they send themselves Valentine’s Day gifts -- they may feel lonely and unloved but at least they will get something nice.

A vendor arranges roses for sale the day before Valentine's Day in a flower market in Manila February 13, 2008. REUTERS/Romeo Ranoco

British lovers ought to steer clear of Paris as a Valentine destination -- one in three picked the French capital as the city most likely to cause them to argue on a romantic break.

It’s the time of year again when love is in the air -- or at least the pressure is on to show you really, really care on February 14.

Surveys abound on what makes the perfect gift -- usually commissioned by a company trying to sell its Valentine wares -- but the way the big day for lovers is celebrated around the world could not be more different.

Saudi Arabia has banned red roses ahead of Valentine’s Day, forcing couples in the conservative Muslim nation to think of new ways to show their love.

The Commission for the Promotion of Virtue and Prevention of Vice ordered florists and gift shop owners in the capital Riyadh to remove any items coloured scarlet which is widely seen as symbolising love, newspapers reported.

Violence in Naivasha, Kenya’s key flower-producing town, has threatened the industry in the key period leading up to Valentine’s Day but growers hope the damage will be limited.

They are also keeping their fingers crossed in the Netherlands.

Dutch auction house FloraHolland, the world’s biggest flower auctioneer, still expects bumper sales in the run-up to the big day as romantic impulses outweigh worries about the health of the global economy.

It all used to be so simple -- buy your lover chocolates, roses or, if you are feeling very generous, diamonds.

But what if the diamonds financed wars, the cocoa beans were harvested by children and the roses grown in a pesticide mist?

“Most roses in the U.S. are grown in Latin America. And they are grown in a way that uses a lot of chemicals,” said Rene Ebersole at the environmental Audubon Magazine.

Ivory Coast, which grows 40 percent of the world’s cocoa, has a persistent child labour problem, a U.S. State Department human rights report said.

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Then what about blood diamonds -- the term referring to gems mined under brutal conditions and sold to support a war effort?

However, incorrigible bookmaker Ladbrokes believe that caution could still be thrown to the wind on the big day.

They are offering odds of 2-1 that Prince William will go down on bended knee and crown his on-off affair with girlfriend Kate Middleton by proposing.

Though of course this is a Leap Year, so if the future king doesn’t get the job done on February 14, tradition dictates that Middleton can ask him to marry her on February 29.