BRUSSELS (Reuters) -Secretary of State Hillary Clinton said on Wednesday it was crucial that NATO allies stick to their commitments to fund Afghanistan's security forces after Western forces end their combat role in the country in 2014.

Afghanistan's foreign backers have pledged $4.1 billion per year to fund Afghan security forces after 2014, but there have been concerns expressed that austerity-hit European countries may not be able to meet their commitments.

"It will be crucial for every nation to follow through on their commitments, and for those who haven't yet committed any funding to do so," Clinton told a meeting in Brussels of NATO foreign ministers and countries contributing to the NATO-led military mission in Afghanistan.

(Reporting by David Brunnstrom)