But it came under pressure in Europe as central banks sold greenbacks to buy euros and diversify.

Plavnik had heard Citi's spot FX desk had a large order to buy euros at the fix.

Is it better to buy euros or dollars now or wait to see which way the vote goes?

The difference here is that pressure has been upward, with central banks forced to buy euros to hold the pegs.

McDarby said there would be strong interest from UK importers to sell sterling and buy euros ahead of the 1.30 euro level.

In a turnabout, the central bank last week sold lats and bought euros.

Yesterday morning the ECB and Europe's national central banks went into the foreign exchange market and bought euros.

William Poole, FX Strategist at FC Exchange, suggested buying euros well in advance might be a good idea.

The SNB has printed Swiss francs like Ben Bernanke, the U.S. Fed Chairman, on speed and bought euros in huge quantities.

In turn they sell some of these dollars in order to have more diversified reserves, buying euros, sterling and yen, among others.

This trend will be underpinned by the Swiss National Bank's policy of buying euros to stop it falling below 1.20 Swiss francs.

Eric Burroughs has a fabulous scoop today: the Swiss National Bank isn't just buying euros at a rate of 1.20 Swiss francs to the euro.