Image copyright European photopress agency Image caption Gun violence has provided Obama with his biggest frustration, he says

President Barack Obama says the tighter gun laws he will announce this week will "save lives" and potentially spare families the agony of bereavement.

The president did not give details of what he will do but he is expected to expand background checks on gun buyers.

He told reporters at the White House that the high number of shootings in the US had forced him to act without the approval of Congress.

Gun supporters are deeply opposed to any new laws.

But Mr Obama said his new measures will be within his legal authority and consistent with the Second Amendment, which grants Americans the right to bear arms.

And while they will not solve every violent crime in the US, he said they will potentially "save lives and spare families the pain".

There are tens of thousands more gun deaths in the US than other countries, he said, including suicides and mass shootings.

Media playback is unsupported on your device Media caption US's ex-top lawyer supports Obama's law but not his methods

The new law, to be passed by executive order without Congress, will mean more sellers having to register as licensed gun dealers, say US media reports.

The president was speaking after hearing recommendations from Attorney General Loretta Lynch, FBI Director James Comey and other top law enforcement officials.

He told the BBC last year that his failure to pass effective gun laws was his biggest regret.

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