The rules surrounding sending a parcel to USA should not be affected, but the US Postal Service has caused controversy after it proposed raising the price of first-class stamps in the country by two cents to $0.46 (£0.30).

In an effort to close the gap on an estimated $7 billion (£4.6 billion) deficit this year, Bloomberg reports that the US Postal Service will also increase its rates for periodicals by eight per cent and catalogues by 5.1 per cent.

The proposed changes will be reviewed by the Postal Regulatory Commission, which has 90 days to make a decision, but if they go ahead the price increases could raise as much as $2.3 billion (£1.5 billion) in the first nine months of 2011.

According to US Postal Service senior vice-president Stephen Kearney, the organisation is allowed to propose raising rates above the rate of inflation under "exceptional or extraordinary" circumstances only.

"We're doing this because the Postal Service really faces a serious risk of financial insolvency," he told the news provider.

In May, the US Postal Service announced realignments within two groups representing key areas of the organisation in an effort to drive revenue growth.