(Reuters) – As the Senate prepares to debate a gun-control bill for the first time in two decades on Monday, Republicans in the House of Representatives are devising ways to delay and weaken gun legislation they see as limiting Americans’ right to bear arms, congressional sources say.

Some Republican lawmakers and strategists are urging House Speaker John Boehner to kill any gun-control bill passed by the Senate by refusing to take action on it.

But the Republican speaker is planning what could be a months-long review of the bill that likely would involve chipping away at gun-related measures in the plan while pushing for proposals to identify and treat the mentally ill as the best hope for a compromise plan to reduce gun violence.

House Republicans’ focus on mentally ill criminals has become sharper in recent days, as a bipartisan plan to expand background checks on prospective gun buyers gained momentum in the Democrat-led Senate – thanks in part to emotional calls for action in Washington by family members of victims of the Newtown, Connecticut, school shooting.

The Senate is expected to vote on Tuesday on that plan, which would expand background checks to include those who try to buy guns online and at gun shows.

Other Senate amendments would ban high-capacity ammunition magazines and military-style “assault” weapons – measures generally seen as having little chance of going anywhere.

The background checks proposal – probably Democratic President Barack Obama’s best chance at getting a significant gun-control bill through Congress – is expected to wind up in the final Senate bill, along with plans to boost funding for school security and tighten restrictions on gun trafficking.

Click here for the full story.