Nearly 60 legislators from the US House of Representatives will travel to Israel this month, which will be funded by the most influential pro-Israel lobby group in the country just before Congress is set to vote over the Iran nuclear accord.

The trip to Israel by 22 Democrats and 36 Republicans is being paid for by the American Israel Education Foundation, the charitable arm of the American Israel Public Affairs Committee (AIPAC).

The foundation sponsors the travel to Israel every two years for newly elected House members.

An AIPAC official said the regular trip was planned before there was an expected vote on the nuclear agreement with Iran, and that no lobbying of lawmakers will take place.

However, The Washington Post has confirmed that the trip includes a number of House Democrats that many lobbyists consider critical votes on the nuclear pact.

Congress can vote to reject the nuclear accord, but it would take a two-thirds majority in both the House and Senate to override a presidential veto.

Some Democrats are undecided about whether they would vote in favor or against the agreement but most Republicans already oppose the deal and are attempting to derail it.

Lobby groups on both sides of the issue have launched expensive advocacy campaigns to convince lawmakers to vote in their favor.

AIPAC is one of the staunchest opponents of the nuclear agreement with Iran and is spending about $40 million to run TV advertisements in 35 states urging legislators to vote down the accord.

AIPAC has been criticized for supporting only right-wing Israeli policies and being unrepresentative of most American Jews.