WASHINGTON -- Republican presidential candidate Mitt Romney is releasing his 2011 tax return, though he has been pressured to release many more years of tax forms.

Aides on Friday said ahead of the Romney release that he earned almost $13.7 million last year and paid more than $1.9 million in taxes -- an effective tax rate of 14.1 per cent.

The release comes after a difficult week for Romney in which a leaked, secretly recorded video showed him saying nearly half of the country doesn't pay income taxes.

Romney paid about $3 million in federal income taxes in 2010 -- or 13.9 per cent.

Critics, including President Barack Obama, have urged Romney to follow his father's model. When George Romney ran for president, he released 12 years of tax returns.

Mitt Romney is refusing.