WASHINGTON (AP) — Republican Sen. Marco Rubio says he’s a “no” vote on the sweeping tax package – unless the child tax credit is more generous to low-income families.

The bill would expand the child tax credit to $2,000 from $1,000. The Florida lawmaker wants a further expansion, and his opposition undercuts Republican leaders trying to muscle the tax bill through the Senate next week.

In a conversation with reporters, Rubio did not specify how high he wants the credit to go.

House and Senate leaders have agreed on the bill in principle but are still finalizing the legislation that they plan to unveil Friday.

A spokesman says Republican Mike Lee is another senator who is undecided on the bill.

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